The Quantity on Purchase Order (Qty on PO) won't show up when you export an Excel file from the Product and Services list. The system always follows the default columns. Though, you can use the Product and Services report, then add the Qty on PO column. Here's how:
In the left panel, click on Reports tab.
In the Search (magnifying) box, type Product then, and then choose Product/Service List.
Under Product/Service List Report page, click on Customize button.
In the Rows/Columns drop-down arrow, click Change columns.
Put a check on Qty On PO box.
Click Run report.
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