From the taskbar, type "This PC". This will give you a list of all of your network drives, Box Drive (if you have installed it), Google Drive FileStream, USB drives, etc.
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Search from the taskbar. Type the name of a document (or a keyword from it) into the search box on the taskbar. You'll see results for documents across your PC and OneDrive under Best match for documents .
To add an icon for This PC to your desktop: Select Start > Settings > Personalization > Themes > Desktop icon settings. In the pop-up window, select the check box next to Computer, then select Apply > OK.