How to edit search more view


I want to change the search more field in the orders menu(sale). When I click it a popup appears and I can search in it. But I want to have a dropdown category filter. For example, instead of searching I narrow down the criteria. Then I chose the one I desire.

I have two problems.

  1. I can’t even find the view that is effecting it.
  2. How will I acomplish such a thing if I find the view.