You can configure your products to be hidden so they do not display in the search or product pages but will be still be available to purchase by sharing the direct link to the product page.
This feature is great in a scenario where you only want certain customers to purchase the product or you want to make special pricing available to certain customers.
You can set your product to be hidden by editing your product from the products list and checking the "hidden" check box.
Before setting the product to hidden you should browse to the product page and copy the link so you can share it with your customers you want to have access to the product.
the link will look like https://yoursiteaddress.com/store/your-product-name