Searching won't return anything?

Make sure to use the search that you access from under your member details at the top (the magnifying glass button) and not the search in the top left, as that one is useless for the forum. Change the search type from "All words" to "At least one word" or "Advanced search options". "All words" rarely if ever returns a result, I think it requires that you get a perfect title match but I'm not really sure about what any of them need. All I know is the other options work better.
 
Click on the flag icon under your username at the top and then select an option from the dropdown. You need to be at the top level of the forum or in the right sub-section to find the post you're after. It seems to only show relatively recent posts though. Another way is to click on your username to go to your publicly viewable profile, so that means finding any post of yours and clicking your username there. Near the bottom is a link stating "Access to the whole list of his/her messages." Again, only about 4 pages of posts show for me.
 
Search seems to be totally broken.

Finding any returned results is difficult, and if they do give results, following any of the links results in a thread does not exist page. even though I can browse to the same page.

And these always return nothing:
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