this is base on Show Model Number v 1.00, i'm taking this out from that contribution, seems like this contribution is missing this great feature.

in catalog/admin/categories.php

search:
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p.products_id = p2c.products_id and pd.products_name like '%" . tep_db_input($search) . "%'


replace it with:
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( (pd.products_name like '%" . tep_db_input($search) . "%') || (p.products_model like '%" . tep_db_input($search) . "%') )


save and uplodate, that's it, now you can search products model in the admin search!

thanks to the original creator!

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