Previously, once in a forum, you could enter a thread number at the top of the page. It would limit the search to the forum you were in currently. Each forum had a thread number 1, 2, 3, etc. Now that we've made a centralized page for the search, it creates a need to specify the forum and thread number, otherwise it would return 25 thread #1s, one for each forum.
Thanks,
M*_Darrin