I found a Recent Documents location that is not cleared whenever I run the cleaner on Windows 10. I'm not sure it if it is covered by a setting I'm not using, but I thought I would share it. The recent files show up whenever I search for something that is related to the recent file or has a similar name.
I am able to clear them by deleting the sub-keys in the registry under Computer\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Search\RecentApps,