Outer join doesn work

Question

The prob with this query is, it has to list the pono for grnno,which contains null value,but outer join doesn work on this, and it list values only for grnno that contains value please help to solve this prob
SELECT pv.vendor_name, pv.segment1 vendorid, ph.segment1 pono, pl.line_num,
ph.creation_date po_date, pl.quantity orderqty,
pll.quantity_received, pl.unit_price, rcv.receipt_num grn_no,
rct.creation_date item_recd_date, rct.quantity, ph.currency_code,
item.segment1 itemcode, pl.item_description description,
ph.attribute1 po_type
FROM po_headers_all ph,
po_lines_all pl,
po_vendors pv,
po_line_locations_all pll,
rcv_shipment_headers rcv,
rcv_transactions rct,
mtl_system_items item
WHERE item.inventory_item_id = pl.item_id
AND item.organization_id = pl.org_id
AND ph.authorization_status IN ('APPROVED')
AND NVL (ph.cancel_flag, 'N') = 'N'
AND NVL (pl.cancel_flag, 'N') = 'N'
AND pl.po_header_id = pll.po_header_id
AND pl.po_line_id = pll.po_line_id
AND pl.org_id = pll.org_id
AND rcv.shipment_header_id = rct.shipment_header_id
AND pl.po_header_id = rct.po_header_id
AND rct.po_line_id = pl.po_line_id(+)
AND pl.po_header_id = ph.po_header_id
AND pv.vendor_id = ph.vendor_id(+)
AND TRUNC (ph.creation_date) >= '06-MAY-2006'
AND TRUNC (ph.creation_date) <= '29-MAY-2006'
AND rct.transaction_type = 'RECEIVE'
ORDER BY pono

Answer 1

This is one that always confuses me - do you need to outer join all references to the table? ie :
  1  select d.deptno,d.dname
  2  ,e.empno,e.ename
  3  from dept d,emp e
  4  where d.deptno = e.deptno(+)
  5  and d.dname like '%S%'
  6* and e.ename like '%A%'
SQL> /
    DEPTNO DNAME               EMPNO ENAME
        30 SALES                7499 ALLEN
        30 SALES                7521 WARD
        30 SALES                7654 MARTIN
        30 SALES                7698 BLAKE
        20 RESEARCH             7876 ADAMS
        30 SALES                7900 JAMES
6 rows selected.
SQL> edit
Wrote file afiedt.buf
  1  select d.deptno,d.dname
  2  ,e.empno,e.ename
  3  from dept d,emp e
  4  where d.deptno = e.deptno(+)
  5  and d.dname like '%S%'
  6* and e.ename(+) like '%A%'
SQL> /
    DEPTNO DNAME               EMPNO ENAME
        20 RESEARCH             7876 ADAMS
        30 SALES                7654 MARTIN
        30 SALES                7900 JAMES
        30 SALES                7521 WARD
        30 SALES                7499 ALLEN
        30 SALES                7698 BLAKE
        40 OPERATIONS
        60 TEST
        70 TEST
9 rows selected.