Hey Rick,
Can you clarify where you are trying to limit these items? Are you trying to limit them from appearing in the item list when you add items to a sales order? If so, you are able to customize the item drop down filter to hide items by item name, item type or any other field name in the items table. Item type would be ideal if all of your items are categorized properly because the filter would mostly be automatic. You can set the filter by going to the Grid > step 2 > Item > Advanced > Filters
-- Loi