Who is sponsoring you for your conversion? If you are doing it for a job in Thailand, they should be able to give you a guide as to what to expect.
I did mine a year ago and there was an air law and human factors exam, but I have herd that it now is only an air law exam. Can't confirm it 100% though.
The air law questions come straight from the Air Navigation Act.
http://www.aviation.go.th/Thailaw/AI....E.%202497.pdf