Removing Youtube app search history

I've got a problem with the Youtube app's search history. It contains only two entries and none of the searches done before or after are shown. The app doesn't save the new entries. I tried removing both cache and data for the app, but that didn't help. The 2 entries are restored soon after I log in again. I'd like to remove all entries, or make new entries show up again - I'm happy with either solution.