Use code in this way.
sort internal tables by key as shown below to improve performance of read statement.
Use move corresponding statement because all fields name are identical.
sort it_lfa1 by lifnr.
sort it_eket by ebeln.
loop at it_ekko1 into wa_ekko1.
Move corresponding.......to wa_final
loop at it_ekpo into wa_ekpo where ebeln = wa_ekko1-ebeln.
Move corresponding.......to wa_final.
read table it_lfa1 into wa_lfa1 with key lifnr = wa_ekko1-lifnr binary search.
Move corresponding.......to wa_final..
read table it_eket into wa_eket with key ebeln = wa_ekko1-ebeln binary search.
Move corresponding........to wa_final
append wa_final to it_final.
clear wa_final
endloop.
endloop.
if any doubts please ask.
Thanks,
vidyasagar