data normalization

[Jabar]

Hello community,

I have table for order record (called invoice). But for every item selected I made columns (Item ID, description, Qnty, price & amount). The issue now if I want to record more than 1 item for same record, I duplicated these columns 13 times so I can record 13 items at one invoice. the table is very big and making calculation cells is time consuming and repetitive work. is there a way to separate data or normalize them for easy app. 

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