That is how I found it, but I think the admins might want to know about bugs (and this seems like the closest to a relevant forum?) (The search has the advantage above Google that it does not include the other parts of the site, which is hard to exclude since Google seems to have dropped "inurl:")Rather use google to search, you'll get better results.
Just select your content under your name...Indeed, the MyBB search function has always sucked, but in the past, I could at least find all of my own posts through my profile page. Now, I go to my profile, click the "Find" dropdown, choose "Find all content by ros_b" and it yields 3 results. When clearly, I have posted more than that. If I do general search by member, I get the same 3 posts. This is really frustrating!