Make sure you are logged in as a user with administration rights and technical features activated.

Go to: Settings -> Technical -> User Interface -> Views

Search for the view with view type 'Search' and for the object you want to change the search behaviour (in your case that might be sale.order or quotation, etc)

Duplicate the view and edit it:

• Change the View Name (to whatever you like)
• Set Inherited View to the exact view you just duplicated

• Edit the Architecture as follows:

  1. Add a xpath tag arround the outer <search> tag with expr="/search" and position="replace".
  2. Add a domain attribute inside the field tag for those fields you want to change the behaviour.

Example for Partner Search View:

<?xml version="1.0"?> 
    <xpath expr="/search" position="replace"> 
        <search string="Search Partner"> 
            <field name="name" string="Name" domain="[('is_company','=',True),]" filter_domain="['|','|',('name','ilike',self),('parent_id','ilike',self),('ref','=',self)]"/>
                ... other fields and filters ...
        </search> 
    </xpath>

• Save the new View and try it.

You might find the documentation helpful.

Regards.