One of the greatest features of Odoo's developer tools is that you can hover over any field in a form and see important information about that field. For our example, we are going to hover over the Source Document field to learn how this field is represented within Odoo's database:

As you can see, the Field name for the Source Document in the sales order is origin. We can also verify that this field belongs to the sale.order object and it is of the type char.

We will use this information to modify the search view so that we can add the ability to search for a source document in the list view without using an advanced search.