Yeah, it is a little wierd. Sometimes I have to try a couple of different options. Once you realize how it works, you know what to search for. Like for instance, if you want to look for AMVs, you won't find anything if you just type AMV (for titles only rather than body of text), you have to type AMVs because not adding the s makes it think it's a different word.
and that's another thing…you'll get more results searching for something in a whole post rather than just thread titles alone, but then if you want to narrow it down, search titles.
btw, maybe someone will take a crack at this.
I really don't think it's THAT hard though, I usually find things pretty easily.