Yes, you can!
To shop a specific refurbisher's store: just click on a listing from a seller you like, and you'll find the refurbisher's name listed to the right of the product, below the red "Buy" button in the green-outlined box. Click on the refurbisher's name and it will take you directly to their shop, where you'll find all of their listings, customer reviews, their Backers Satisfaction score, and their About Me.
You can also find the seller's shop by opening up the My Orders tab in your BackMarket.com account, clicking on "Show more details" under the listing of the seller you like, and voila! The seller's store is linked on the left.