Can someone tell me what's up with Facebook?

I’m looking for my daughter to send her a message and I know, beyond a doubt, that she’s there(she used my computer just today to get on there for a while) but for the life of me I can’t find her! My son either! Or anyone else I started doing a search for (that I have listed as my friends even) just to test the thing.

Have they changed the search parameters or something?