When loading an existing purchase order, the Order rows are shown in a table in the lower section of the window.
If the EDI order responses are imported by using the Order header button, here you will see the order header rows. If you use the Order rows button, you will see the order response for each order row.
If the import file contains several different order responses and all have been imported, the order rows are separated into different order responses to the left in the table. You can also see that the order header information changes when you move the cursor between order rows that belong to different orders.