Extractor 0CO_OM_CCA_9 and BSEG

Hi All, We are using the extractor 0CO_OM_CCA_9 and getting some fields from BSEG table using the below code : SELECT SINGLE GEBER         INTO (L_BIW_0CO_OM_CCA_9-GEBER)         FROM BSEG       WHERE BUKRS = L_BIW_0CO_OM_CCA_9-REFBK         AND BELNR = L_BIW_0CO_OM_CCA_9-ZZFIBELNR         AND GJAHR = L_BIW_0CO_OM_CCA_9-REFGJ         AND BUZEI = L_BIW_0CO_OM_CCA_9-REFBZ. We are facing the issue for one value of field REFBZ which does not exist in the table BSEG. But this value can be found in the table COVP Under the field REFBZ. In the COVP table there are some différents values for REFBZ and REFBZ_FI. Can you please tell me if i need to use the field REFBZ_FI instead of REFBZ in the above abap code ?. Help is greatly appreciated Thanks and Regards Matihi