Problem in select query

Hi Gurus,

I am selecting from EKBE table for all entries from table LIPS where I am passing VGBEL as selection parameter to EKBE and BEWTP as E. here case is for one delivery one line item is partially GRed hence generated 2 records in EKBE for line item say 50, and EBELN as 12345. Now when I select from this EKBE where ebeln as 12345 and bewtp as E I am only getting 5 records for not 6, where there are 2 records for line item 50

what could be the possible reason for not selecting both records of quantity 2 each but selecting 1 record of quantity 4.