MAJOR Problems with iTunes File Finding System!

Earlier today, I asked a question about how to mass-update files in iTunes. But now that I'm going over different other tracks and albums that are out of sorts, there are some major problems I'm running into.

Sometimes it will ask me if I want to iTunes to find all, but then it won't find any--even though they're right there, in the same folder! Also, it keeps defaulting to this one album and doesn't start the search from the last album I updated.

This is all so incredibly frustrating and maddening. How do I get this feature working correctly again?? Please help!