From the Connect Accounts page you can view all of the files/folders that have been synced to Shelf. You can either select the connect account button from the Shelf dashboard or click on the touchpad (orange ADD button) and select import cloud accounts to navigate to the page.
On the page you should see three sections: Connected Clouds, Connect Your Accounts, and One-Time Import. The accounts listed under Connected Clouds will show what accounts you have connected to Shelf and if you click on an account a drop down menu will appear of all of the files from that account that you have synced to Shelf. If the Connected Clouds section doesn’t appear that means you haven't synced any cloud accounts to Shelf.