I typically place GS on one screen and use a browser of the other screen to research categories and items.
If you navigate to a item listed on eBay a cookie crumb navigation bar will be shown at the top.
Pottery & Glass > Pottery & China > Art Pottery > Brush/Brush-McCoy
Clicking on Brush/Brush-McCoy takes you to:
It would be nice to drag or copy and paste the breadcrumb navigation bar (Pottery & Glass > Pottery & China > Art Pottery > Brush/Brush-McCoy) or its URL (https://www.ebay.com/b/Brush-Brush-McCoy-Art-Pottery/18895/bn_16562162) into the category fields in GS to autmatically set those.
This would be faster than searching, especially for categories that often share the same words - you are left visually scanning through the search results. This would be faster than trying to manuualy navigate to the same category within GS.