Hi Wanda,
unfortunately I cannot tell you right now how to read multiple fields from table (KNVP) with this module but I'm aware that you should not use this function module directly as SAP has stated that there are some limitations as outlined in SAP note 382318 (FAQ | Function module RFC_READ_TABLE):

Why is it necessary to extract data with the help of this function module? If you just want to extract several fields from table KNVP you could go the "standard" QUERY way!?
Thanks and regards
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Dominik Lind
IT consultant
K+S Aktiengesellschaft
Kassel
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