android app having different orientation for its items when changing the screen

My items on large screen like 10.1 works fine and every item in its position but if I change the screen to 4 or 3, some of my items disappear and some appear in large font related to the device screen, so I want it to appear all items on its correct positions so if the app run on small screen the font small and every thing in its normal position, also with large screen. So what I have to do to my xml to get my goal?

this is my xml :

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:fillViewport="false"
android:fadingEdge="none"
android:background="#BFAF80"
android:scrollbars="none"
android:scrollbarSize="0dp"
android:paddingRight="0dp"
android:scrollbarAlwaysDrawVerticalTrack="false"
android:scrollbarStyle="insideOverlay"
>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#BFAF80"
android:id="@+id/CreatClear"
android:orientation="vertical">

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/Bwt"
    android:textStyle="bold"
    android:gravity="center"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginTop="29dp"
    android:hint="@string/body_weight"
    android:textColor="#e53f3f3f" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/Age"
    android:textStyle="bold"
    android:gravity="center"
    android:hint="@string/age_years"
    android:layout_below="@+id/Hit"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:textColor="#e53f3f3f" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/Screat"
    android:gravity="center"
    android:textStyle="bold"
    android:hint="@string/serum_creatinine"
    android:layout_below="@+id/Age"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:textColor="#e53f3f3f" />

<CheckBox
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Female"
    android:id="@+id/Cfemale"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:textSize="@dimen/abc_text_size_medium_material"
    android:layout_marginTop="28dp"
    android:layout_below="@+id/Screat"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

<CheckBox
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Male"
    android:id="@+id/Cmale"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:textSize="@dimen/abc_text_size_medium_material"
    android:layout_below="@+id/Cfemale"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

<TextView
    android:layout_width="64dp"
    android:layout_height="64dp"
    android:id="@+id/calcH"
    android:background="@drawable/ic_launcher5"
    android:clickable="false"
    android:gravity="center"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true" />

<TextView
    android:layout_width="64dp"
    android:layout_height="64dp"
    android:id="@+id/calc"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:background="@drawable/ic_launcher"
    android:clickable="true"
    android:gravity="center" />

<TextView
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:text="Reset"
    android:id="@+id/clearH"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:background="@drawable/ic_launcher5"
    android:clickable="false"
    android:gravity="center"
    android:layout_alignBottom="@+id/sex"
    android:layout_toLeftOf="@+id/sexa1"
    android:layout_toStartOf="@+id/sexa1" />

<TextView
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:text="Reset"
    android:id="@+id/clear"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:background="@drawable/ic_launcher3"
    android:clickable="true"
    android:gravity="center"
    android:layout_alignTop="@+id/clearH"
    android:layout_alignLeft="@+id/clearH"
    android:layout_alignStart="@+id/clearH" />

<TextView
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:text="Menu"
    android:id="@+id/menuH"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:background="@drawable/ic_launcher5"
    android:clickable="false"
    android:gravity="center"
    android:layout_alignParentBottom="true"
    android:layout_toRightOf="@+id/sex"
    android:layout_toEndOf="@+id/sex" />

<TextView
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:text="Menu"
    android:id="@+id/menu"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:background="@drawable/ic_launcher3"
    android:clickable="true"
    android:gravity="center"
    android:layout_alignParentBottom="true"
    android:layout_toRightOf="@+id/sex"
    android:layout_toEndOf="@+id/sex" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/Hit"
    android:textStyle="bold"
    android:gravity="center"
    android:hint="@string/height_cm"
    android:layout_below="@+id/Bwt"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:textColor="#e53f3f3f"/>

<TextView
    style="@style/TextAppearance.AppCompat.Medium"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:id="@+id/Serum"
    android:gravity="center"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:textSize="@dimen/abc_text_size_large_material"
    android:lines="@integer/abc_max_action_buttons"
    android:autoText="false"
    android:background="@color/ripple_material_dark"
    android:layout_above="@+id/blank"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

<TextView
    style="@style/TextAppearance.AppCompat.Medium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/newSerum"
    android:gravity="center"
    android:textColor="#e53f3f3f"
    android:textStyle="bold"
    android:textSize="@dimen/abc_text_size_large_material"
    android:layout_above="@+id/calcH"
    android:layout_centerHorizontal="true"
    android:visibility="visible"
    android:lines="@integer/abc_max_action_buttons"
    android:background="@color/ripple_material_dark" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceSmall"
    android:text="nIBW"
    android:id="@+id/nIBW"
    android:layout_below="@+id/Cmale"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true"
    android:layout_marginRight="15dp"
    android:layout_marginEnd="15dp"
    android:layout_marginTop="34dp"
    android:visibility="invisible" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceSmall"
    android:text="nABW"
    android:id="@+id/nABW"
    android:layout_alignBottom="@+id/nIBW"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true"
    android:visibility="invisible" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/sex"
    android:layout_alignTop="@+id/Cfemale"
    android:layout_toRightOf="@+id/Screat"
    android:layout_toEndOf="@+id/Screat"
    android:gravity="center"
    android:text="Gender"
    android:visibility="invisible"
    android:layout_alignParentLeft="true"
    android:layout_marginLeft="0dp"
    android:layout_alignParentTop="true"
    android:layout_marginTop="604dp" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/sexa1"
    android:gravity="center"
    android:text="Gender1"
    android:visibility="invisible"
    android:layout_alignTop="@+id/Cfemale"
    android:layout_alignRight="@+id/nIBW"
    android:layout_alignEnd="@+id/nIBW" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/sexa2"
    android:gravity="center"
    android:text="Gender2"
    android:visibility="invisible"
    android:layout_alignTop="@+id/sexa1"
    android:layout_alignRight="@+id/sexa1"
    android:layout_alignEnd="@+id/sexa1" />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:inputType="numberDecimal"
    android:ems="10"
    android:id="@+id/BSA"
    android:gravity="center"
    android:text="Body Surface Area"
    android:visibility="invisible"
    android:layout_below="@+id/Cmale"
    android:layout_toLeftOf="@+id/nABW"
    android:layout_toStartOf="@+id/nABW" />

<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:id="@+id/blank"
    android:layout_above="@+id/newSerum"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

<TextView
    style="@style/TextAppearance.AppCompat.Medium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Creat Clear (ml/min)"
    android:id="@+id/HSerum"
    android:gravity="center"
    android:textColor="#ffffffff"
    android:textStyle="bold"
    android:background="@color/background_material_dark"
    android:textSize="@dimen/abc_text_size_large_material"
    android:layout_alignTop="@+id/BSA"
    android:layout_toRightOf="@+id/Screat"
    android:layout_toEndOf="@+id/Screat"
    android:visibility="invisible" />

</RelativeLayout>
</ScrollView>

Create a some resource directories called values-swXXXdp in res folder where XXX means smallest screen witdh.

In each directory create a file called dimens.xml and define the dimension for each swXXXdp:

<dimen name="custom_width">40dp</dimen>

Then, to retrieve that value in xml do the following: for example the width of a view:

android:layout_width="@dimen/custom_width"