Windows 10 Block C: and UNC from the search bar

I am trying to setup Windows 10 Education for my domain and am having issues with the search bar. I have locked down the All Apps section and use a redirected desktop to a UNC share for the application shortcuts. However, I want the users to be able to use the basic search. I have tued off cortana and web search via GPO and I have set the "Remove Run Menu from Start Menu" GPO to enabled. Which does prevent UNC share access in an open Window and C: access but if you place C: or a UNC share path into the Windows 10 search on the task bar you still have access.

At present I have local My documents folder because they use large applications like Photoshop CC and it works better when running from the local My documents and then copying to a networked home folder when they are finished. I have denied access to the C: under the GPO for User Config → Admin Temp → Windows Components → File Explorer → "Prevent access to drives from My Computer" but whilst this stops all access to C: it then means you cant use local My documents and sadly UNC paths are still able to be browsed to through the search.

Has anyone come across this issue so far. I have tried looking at blogs and Google searches but the only stuff out there points to the GPO's I have already mentioned which don't stop UNC from search.

Any help would be greatly appreciated