That screen is to select the products you want to be able to sync to the WSUS. Only after an update by a new vendor is published will you see that new vendor listed in that view from your screenshot. Say if you were to publish a Java update, once that update finishes publishing you will be able to select 'Manage Products' and see "Sun Microsystems" as a new option to check and sync. Let us know if this answers your question.
But how I can add more products ? for example Adobe Photoshop 15 and InDesign it not listed