<search string="Search Scrap">
                    <field name="name" string="Reference"/>
                    <field name="product_id"/>
                    <field name="location_id"/>
                    <field name="scrap_location_id"/>
                    <field name="create_date"/>
                    <group expand="0" string="Group By">
                        <filter string="Product" name="product" domain="[]" context="{'group_by':'product_id'}"/>
                        <filter string="Location" name="location" domain="[]" context="{'group_by':'location_id'}"/>
                        <filter string="Scrap Location" name="scrap_location" domain="[]" context="{'group_by':'scrap_location_id'}"/>
                        <filter string="Transfer" name="transfer" domain="[]" context="{'group_by':'picking_id'}"/>
                    </group>
                </search>