Is there any methods to retrieve deleted records from a mysql database?
No.
Deleted records are gone (or munged so badly you can't recover them). If you have autocommit turned on, the system commits each statement as you complete it (if you have auto commit turned off, then do a rollback NOW - phew, you're saved -- but you are running with autocommit, aren't you?).
One other approach is to reply the activity that created the missing records - can you do that? You can either re-run whatever programs did the updates, or replay them from a binary log (if you still have the binary log). That may not be possible, of course.
So you need to recover the data from somewhere - either a backup of your db (made using mysqldump) or of your file system (the data files of MyISAM tables are all simply structured and on the disk - recovering InnoDB tables are complicated by the shared use of ibdata files).