It works! Thank you!
I have another question. :D
With all the Voucher had SO Number, i've copied SO #, DO #, DO Date from another worksheet. Now i want to return the Voucher Amount and sum it based on SO # and DO Date.
Some Amount is for several DO, thus it didn't need to add from the previous amount. Just return the same amount as the previous one. In other words: Different DO, same DO Date, same amount.
I used lookup:
But some amount didn't showed up! And i've used sumif to sum the amount, but it didn't work! 
I'm sorry if it's confusing. Thank you.
PS: Can i post the question here? Or should i make another thread, since this is the excel programming sub forum. And here's the example.
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