You can choose to create an indirect join via the Products table to the Delivery alternatives table. This will cause the supplier's product number and description to be called up in the order entry window. An indirect join means that you can join a page element to all of the underlying tables on an unlimited number of levels. As the order lines contain references to the Products table, you can for example join stock balances to order lines.
If there are several references to the same underlying table, or from a related table, select a current foreign key. You can see that in the list in the bottom left-hand corner of the dialog box. You can also select it and press OK or Enter. If you can only see one foreign key, you can double-click directly on the underlying table or the related table. You can also select the element here and click OK or Enter.