Interactive report {get crusor} not working

Hi,

     I am new to SAP ABAP . I have one custom report in first level . In basic list  click  on particular field  like  "matnr" the it will goes to secondary  .in how to implement get cursor .

any one  send me   " get cursor  "

Basic list :

  LOOP AT it_final into wa_final.

      write:/2 wa_final-matnr,

             18 wa_final-maktx,

             62 wa_final-werks,

             75 wa_final-lgort,

             95 wa_final-ersda,

             110 wa_final-mtart,

             125 wa_final-matkl,

             135 wa_final-NTGEW,

             150 wa_final-BRGEW.

      hide wa_final-matnr.

endloop.                                                        

secndary list

  IF it_final is not initial.

    select MATNR

           BWKEY

           VPRSV

           LBKUM

           VERPR

           STPRS

           PEINH

           STPRV from mbew into table IT_MBEW

          where matnr = wa_final-matnr.

  ENDIF.

how to pass the get cursor field  in my second select query