I tried searching under my username and specifying “search title only” instead of “search entire thread” – but my search still called up every thread on which I had submitted any posts in the specified time period. If I want to search for only those threads I started myself, what should I do?
“search title only” searches only for the search terms you specify in the title text. Since your user name isn’t there, it won’t work. There’s no way to do what you propose without modifying vBulletin, and the management has stated repeatedly they won’t do that without a very good reason. You could bookmark the threads you start.
You could search for your username and sort the results by poster. That way, the other threads you posted in still show up, but those you started are next to each other in the list.
This subject was discussed here.
In that thread, it was not determined if you could or not, (most likely not) but there were suggestions that might be able to help you.