How do u.s customs search you?

Question

what do they do if you get searched?

Answer 1

If there is cause, they could do a strip search which is usually the next step towards jail.

Answer 2

If you're chosen randomly to be searched they will take you in a private room and go through your bags, thoroughly!  They'll ask you a lot of questions, like why you did you go to that country, etc.  They will run a wand over your body and maybe even pat you down.  It's no fun!