OK, so I think I learned what I needed to learn about the "fucking filters," and I added this to the first message of the FAQ.
The Filter
(searching by thread title)
Toward the top of the Mudcat Forum main menu (click here), you'll see a "filter" box - put an appropriate word in the box and set the age to whatever is appropriate to cover the period you want to search. Click the grey "reset" button, and all threads with that word in the title should appear (a "thread" is a series of forum messages, posted on a specific topic). Here's a filter box you can try: