Scenario:

Inbound EDI 850 purchase order can contain multiple item numbers. We are looking to capture multiple item numbers, in PO107, PO109 and PO111. We capture the data based on the qualifiers in PO106, PO108, and PO110.

Solution:

Create 3 instances of the PO107 element, attach 3 separate fields to each PO107 element. We will then qualify each of the PO107 elements based on the qualifiers that can possibly appear in PO106, PO108, and PO110.
In the example below we are qualifying the PO108 with 'SK'. Note that we placed a '2' into the 'incr' field.
By scanning every other segment we can capture the respective values.