Query to find pending for Receiving quantity against the PO and Release NO

/* Pending for Receiving Details */

SELECT   HOU.NAME ORG_NAME,
         pra.AUTHORIZATION_STATUS,
         PHA.SEGMENT1 PO_NUMBER,
         PRA.RELEASE_NUM,
         PLA.LINE_NUM,
         MSIB.SEGMENT1 PARTNO,
         MSIB.DESCRIPTION PARTDESC,
         PV.SEGMENT1 VENDOR_NUMBER,
         PV.VENDOR_NAME,
         PLLA.QUANTITY ORDer_QTY,
         PRA.APPROVED_DATE,
         TRUNC (pra.creation_date) APPROVED_DATE,
         ( (PLLA.QUANTITY - PLLA.QUANTITY_RECEIVED) - PLLA.QUANTITY_CANCELLED)
            PENDINGORDQTY,
         (SELECT   SUM (NVL (rsl.quantity_shipped, 0))
            FROM   RCV_SHIPMENT_LINES RSL, PO_LINE_LOCATIONS_ALL PLSA      --,
           WHERE       RSL.po_line_location_id = PLSA.line_location_id
                   AND PLSA.SHIPMENT_NUM = PLLA.SHIPMENT_NUM
                   AND rsl.PO_RELEASE_ID = plla.PO_RELEASE_ID)
            SHIPPED_QUANTITY,
         PLLA.QUANTITY_RECEIVED,
         PLLA.NEED_BY_DATE                                                 --,
  FROM   PO_HEADERS_ALL PHA,
         PO_LINES_ALL PLA,
         HR_OPERATING_UNITS HOU,
         PO_LINE_LOCATIONS_ALL PLLA,
         PO_RELEASES_ALL PRA,
         PO_VENDORS PV,
         MTL_SYSTEM_ITEMS_B MSIB
 WHERE                                           ------PHA.SEGMENT1 = '101358'
             ------AND PRA.RELEASE_NUM = 5
             PHA.PO_HEADER_ID = PLA.PO_HEADER_ID
         AND PLLA.PO_HEADER_ID = PHA.PO_HEADER_ID
         AND PLLA.PO_LINE_ID = PLA.PO_LINE_ID
         AND PLA.ORG_ID = HOU.ORGANIZATION_ID
         AND PRA.PO_RELEASE_ID = PLLA.PO_RELEASE_ID
         AND PHA.VENDOR_ID = PV.VENDOR_ID
         AND MSIB.INVENTORY_ITEM_ID = PLA.ITEM_ID
         AND MSIB.ORGANIZATION_ID = PLLA.SHIP_TO_ORGANIZATION_ID
         AND PLA.ORG_ID = NVL (:P_ORG_ID, PLA.ORG_ID)
         AND PV.VENDOR_ID = NVL (:P_VENDOR, PV.VENDOR_ID)
         AND MSIB.INVENTORY_ITEM_ID = NVL (:P_ITEM, MSIB.INVENTORY_ITEM_ID)
         AND ( (PLLA.QUANTITY - PLLA.QUANTITY_RECEIVED)
              - PLLA.QUANTITY_CANCELLED) > 0