The Searchanise add-on doesn't index products with Status = Hidden. So you can change the product's Status to Hidden for products in the CS-cart administration panel to hide them from search.

Note
The product's Status set to Hidden in CS-Cart means that the product does not appear in the product list in the storefront, and customers can reach a hidden product via a direct link only. So products with this status will be hidden not only from the search, but from category pages eigher.

To set up the Hidden status for a product, follow these steps:

  1. Go to the CS-Cart administration panel > Products > Products.
  2. Click on the name of the product you’d like to edit.
  3. Set the Status to Hidden. 
  4. Save changes.

That's all. You can go to your storefront and make sure that the product doesn't appear in the search results.