BOM extract

Written  sql  for adhoc report as given below it works for few BOMS and for others it's a issue like it extracts extra component though it is not shown in Indented Bill form

SELECT DISTINCT SUBSTRB(C.SEGMENT1,1,20) ASSYITEM,
       LEVEL BOM_LEVEL,
       SUBSTRB(D.SEGMENT1,1,20) COMPITEM,
       --C.DESCRIPTION ASSEMBLY_DESCRIPTION,
       --C.PRIMARY_UOM_CODE "ASSEMBLY_UOM",
       REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(D.DESCRIPTION,'&','&'),'<','<'),'>','>'),'"','''),'''','"') COMPONENT_DESCRIPTION,
       D.PRIMARY_UOM_CODE COMPONENT_UOM,
       D.ATTRIBUTE3 SCHEDULE_B,
       D.ATTRIBUTE4 COUNTRY_OF_ORIGN,
       D.ITEM_TYPE,