if by that you mean add products to the ticket's invoice (pc, screen, cables etc), that`s possible.
First you add the products in your domain/products.php and then in invoice, under the item if you start type the name of the product, will auto-suggest from the list, then select what you need, and it will auto complete the invoice row with product name, description and price, you only need to adjust the quantity.
i hope this answers your question