qBittorrent official forums

I can't seem to find an option where I can see all of the messages started by a specific user (say mine) or see all the messages that a user was involved in.

I tried to use the search tab, but it requires some text to search for.

Is there a way to do this?

Do you mean previous searches? qbt doesn't save those.

Click user name to go to profile, then click "Show Posts" on the left.

And select  "Topics"  from the sub menu.

ALSO

If you use the search page and put the username in the "By user:" field with a specific word in the "Search for:" field.