FRM-40350 Query Caused No Records To Be Retrieved in oracle 10g Forms,but data exists in the table

Hi All,

In 10 g forms i am trying to fetch the data from FIND BLOCK using FIND button to the main block.

There is data in the table but not able to fetch using below code.Getting the "FRM-40350 Query Caused No Records To Be Retrieved".

here is the code i use to get the details of purchase order in the find block find button when button pressed trigger.

SELECT  INTERFACE_HEADER_ID INTO L_INTERFACE_HEADER_ID FROM JEG_PO_HDRS_INT_RECON WHERE DOCUMENT_NUM = :PO_QF.po_num_qf;

set_block_property('JEG_PO_HEADERS_INTERFACE', default_where, ' where :JEG_PO_HEADERS_INTERFACE.po_num = '||''''||:PO_QF.po_num_qf||''''||'and'||' :JEG_PO_HEADERS_INTERFACE.interface_header_id = '||''''||l_interface_header_id||'''') ;