You can remove individual items from your browsing history by going to your History tab and clicking the X icon on the top-right of each product you want to remove.
You can also clear your product history completely by going to your profile and clicking "clear my product history" at the bottom of the page.
If there are any products in particular that you'd like to keep an eye on before you clear your entire history, you can save favorites by clicking the product link and then selecting "Add to Watchlist" on the main Capital One Shopping product page.