My ex abanded my two daughters 4 years ago.to an abusive couple.six mounths later I found out where my girls were and went and picked them up.how can I get her for child abandoment...

As soon as you found them, you would have called the police and reported it.

You also use this to get custody and/or child visits changed to give you more rights and more protection for the kids from him. Using your CPS or police report about this as your evidence.