Do the recording(SHDB) in such a way that it accepts multiple values for Invoice numbers in the Selection screen.
Hope this code might be useful:
LOOP AT belnr_lt INTO belnr_ls.
idx = sy-tabix.
CONCATENATE ''RSCSEL-SLOW_I(' idx ')' belnr_ls INTO fnam.
PERFORM bdc_field USING 'BDC_CURSOR'
fnam.
ENDLOOP.
Regards,
Sowmya