How do I get the exact pick location in my delivery order screen? Now it only shows “wh/stock” for every product I need to pick. And not the exact location like “wh/stock/shelf123”. What setting do I need to make to get an exact location of the product ordered?

I use version Odoo 8 with modules Inventory, Sales and Invoices.

(please don’t close this question when it seems not enough information is provided. I will gladly provide more info)