Folder hidden from spotlight?

I did a search, trying to locate a folder that I knew was on my hard drive. It didn't come up. A friend told me some work arounds, and I eventually found it by other means. But I'm wondering - did I use spotlight incorrectly? All I did was to enter the folder name in the search field (the folder was under ~/Library/Application Support, if that makes a difference).

No, that would be a system folder.

Here is a tut on searching through system folders.- link

Do you mean all folders under that directory are hidden? And how do I set up Spotlight to show all folders?

Oh, I see you've edited your post. The tut worked - thanks!