I tried to use the forum search bar several times, but each time it returned results (posts) from about 10 years ago, after which I don't even think about using the search.
Searching help.
With forum search tool, you can customize it with Message age and if you only want to get results in the last 1 year, set it as between 0 and 365 days. Increase the number to the one for 2 years, 3 years for example.
Message age sets the minimum and maximum ages of posts to search.