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,
I'm not sure if you are talking about recent files ir recent apps?
That registry entry though indicates recent apps.
I assume that you haven't got the Creators Update yet?
With the Creators Update you have more control of the start menu.
Among other things you can-
Turn off the display of Recent Apps altogether. (Which modifies that registry key so it has no entries).
Turn off the whole annoying display of the Apps list on the start menu so that they are minimised to a small button at the top left.
The settings are found in Settings>Personalisation>Start