Molly, the problem is that different places you search in give different results and you can look at the examples in this thread to see this. Even if there is a good reason for this, you can't expect users to realize what each box does. I can assure you that I won't remember what each one does. Until now, when I wanted to search for something, I would open the advanced page from my favorites menu. In the current situation, when I will want to search for something, I won't bother thinking about boards and threads - I will just go to the box at the top of the page, because that's the one that works.
There are several problems with this:
1) I want an advanced search page. I like being able to see my options and not having to worry about syntax.
2) I don't search for things only inside the forums. I may want to recieve results like KB articles and examples within the same search.
3) I'm not the only user around. You can see that even JLV didn't notice that box, and even if he had, there's no reason for him to know it's different. This way, even those users who do try searching for an answer before posting a question won't find what they're looking for and will post what would arguably be an unnecessary question (like all the basic question about property nodes, although I presume that people that post these kinds of questions haven't done their homework well, for whatever reason, and usually don't bother searching for the answer anyway). Also, as said, this prevents veteran users from finding their old answers.
I think this is the longest post I ever posted here. That is how much this troubles me (and other users).
___________________
Try to take over the world!