searching past posts

You're not doing anything wrong. It's a glitch in the search system. If your search results are more than one page, you cannot see the additional pages.

I normally try to narrow my search so that only one page of posts (or less) are recalled.

Hope this helps,

When I search the forums, it always finds every single message specified in the time period specified regardless what the search term is. Am I doing something wrong?

No you're not doing anything wrong. The search isn't working right now and just returns everything within the time period. It's on my "to fix" list.