In order to save and manage search results in Primo, make sure you sign in first! Otherwise everything will disappear when you close your internet browser.
Conduct a search in Primo. When you see an item you want to save, click on the Pin icon.
As you save items, the pin in the upper right-hand corner will glow red. Click on that pin to see everything you've saved.
These items will stay in your Favorites until you delete them.