Need vba code to use vlookup to take data from three sheets

Heloo

I have attached excel as sample for your review. Also i rewrite the requirement as below

In the attached excel there is three sheets
Mainbook
Data1
Data2

Data 1 and Data 2 sheet has list of details available in the Row with reference in A column as PO#

In Mainbook - Column D will be filled with PO#

Required VBA code to pull the related PO# row details from the DATA1 or in DATA2 sheets.

Hope I clarified the requirment. Please support.

Note: If suppose PO# available as Duplicate in DATA1 and DATA2, kindly show the result as duplicate in Mainbook related row on any of the cell