When you select product while creating quotes/invoices/sales order, all the sub products will be added if the product is a product bundle. Its detailed view will also show all the products i.e. parent and sub products If you want to select only a sub-product, then click on Sub Products link given in the column of Action. It will display the sub-product pop-up from which you can select the sub- products. If the product is not a bundle, it will be shown as Not a Bundle.