If your are looking for a report of purchase orders by user id, use ME80FN. Using Dynamic Selections, select the “created by” option in the Purchasing Document Header. You can then search by one user id or multiple users ids. Select the rest of your criteria as required. Execute. You can then print the report.
If you are looking to print the individual purchase order, you can obtain the list of numbers using the above report, then use ME9F to print the document numbers obtained using ME80FN.