How the search works on Add Products dialog
When you search for a product in the enhanced Add Products dialog while adding products to an opportunity, quote, order, or invoice, the search results are displayed in the following order:
Products that contain the whole searched phrase in the Product Name or Description fields are displayed at the top of the list.
Products that contain at least one of the words from the searched phrase in the Product Name or Description fields are displayed at the bottom of the list.
Both parts are displayed separately and are ordered alphabetically by the Product Name field.