How to Fetch data in newly added tab in migo ?

Hi guys,

I have created a tab name as "other tab" ..in that i have added two field:  invoice item and quantity.

i need to fetch the data in field invoice and quantity....

In Migo tcode we get line items like

Line       Mat. short text      Qty in Une

1               Aluminium               25

so what i want that when i click on any line item   i'll get like aluminum in my  invoice field and 25 in qty field.

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if image is not clear then check attached image..

if it is possible the pls help me out.......................