I just did a test search, after being so surprised when someone pulled a whole thread out of thin air -- with the words "family tree" only.
OMG -- Full text search? on mastodon that is so freeking rare.
On Pleroma she pulled it off easy.
On a smaller instance, ok. On FAB, where my new account is, the same search got results as far back as 3 weeks.
Amizingly, it showed one of Hans's posts, done here on qoto, seen and indexed, retrieved on FAB easily.