Just trying to understand how you have traditionally searched for a specific page. Do you recall certain content from the specific page within the thread that you try searching for? Do you try using the numbered navigation links that can take you directly to a page? You mention only going back 2 or 3 pages at a time, though the page links let you look at several pages ahead or back simply by clicking on them.
Have you tried using the advanced search on this site? There is a down arrow to the right of the search text box that brings up more specific search criteria.