See section 2.4.5: https://software.indexdata.com/zebra/doc/querymodel-rpn.html attr 6=2 'complete subfield' is deprecated and translates to 'complete field' In terms of our implementation this means that you must activate both: TraceCompleteSubfields TraceSubjectSubdivisions otherwise you search the whole field for a match on a partial subfield. Furthermore, for a record with an authority number included the search will fail, e.g.: su,complete-field:"Computer programming." - returns 0 results su,complete-field:"Computer programming 973" - returns correct result