Unable to fetch link between PO and Receipt

Hi,

When I query using the PO in "Query Find" screen for receipts, it fetches records. But when I try to query shipment_header_id, (using "Examine" option) it does not display data.

When I query rcv_shipment_lines_all based on po_header_id, it does not fetch data.

I am unable to get the link between the receipt and the purchase order.

Let me know if I am missing anything.

Thanks,

Krishna