Hey! Cool project, my co-founder told me about this. I suppose you're getting initial traffic from search engines, isn't this just adding an extra step for users as most search engines already display products at first level?
Generally, Google Shopping shows big retailers or ads. E-commerce stores have a tough time competing against these big retailers, on both Google Shopping and a normal Google Search.
That all said, we are running tests to track engagement of a "search result page" indexed by Google or Bing. For example, searching for a "backpack" and then landing on the below link with selection to choose from.