Powerapps: ClearCollect() is not showing all columns filled from Dataverse and showing with schematic name and not real col-header

When I run in Powerapps on a button with a onselect

ClearCollect(colPeopleTEST,
        FirstN(Sort(PER, PERNAME), 30)
)

I get the collection colPeopleTEST in the variables displayed.

Problem is, that all columns start with cr32e... instead of the the real Column name.

I know that this is the schema or logical name, but I have seen a lot of tutorials of other peoples using dataverse as their source and they can query the column by their real-name / column-header.

Also, in the collection, I did not have ALL columns from the dataverse table, and not all columns are filled with data under variables > collections > colPeopleTEST > show Table

What should I do to solve this problem?

In the collections viewer, it will only show the "logical name" of the columns that came from Dataverse. But you can still reference the display names for the columns in your expressions. For example, for this collection that I have:

I can reference the display names of the columns in my expressions:

As far as columns being blank in the variable viewer: by default Power Apps only retrieves the columns that are actually used in the app. In the example above, I wasn't using the columns on the left... But if I start referencing them in some part of my app, for example, by updating the label above (after doing that I had to click the button again to retrieve the newly referenced columns):

Then the newly referenced columns are now retrieved from the server and are part of the collection.