app-odoo/app_purchase_superbar/views/purchase_order_views.xml

<odoo>
  <data>
    <record id="view_purchase_order_filter_superbar" model="ir.ui.view">
        <field name="name">request.quotation.select.superbar</field>
        <field name="model">purchase.order</field>
        <field name="inherit_id" ref="purchase.view_purchase_order_filter"/>
        <field name="arch" type="xml">
            <xpath expr="//search">
                <searchpanel>
                    <field name="company_id" groups="base.group_multi_company" icon="fa-building"/>
                    <field name="partner_id" select="multi"/>
                    <field name="state"/>
                </searchpanel>
            </xpath>
        </field>
    </record>
    <record id="purchase_order_view_search_superbar" model="ir.ui.view">
        <field name="name">purchase.order.select.superbar</field>
        <field name="model">purchase.order</field>
        <field name="inherit_id" ref="purchase.purchase_order_view_search"/>
        <field name="arch" type="xml">
            <xpath expr="//search">
                <searchpanel view_types="list,kanban,pivot,graph">
                    <field name="company_id" groups="base.group_multi_company" icon="fa-building"/>
                    <field name="partner_id" select="multi"/>
                    <field name="invoice_status"/>
                    <field name="state"/>
                </searchpanel>
            </xpath>
        </field>
    </record>
  </data>
</odoo>