rma/product_warranty/views/product_template.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

    <record id="product_template_extend_warranty" model="ir.ui.view">
        <field name="model">product.template</field>
        <field name="inherit_id"
               ref="product.product_template_form_view"/>
        <field name="arch" type="xml">
            <page name="sales" position="inside">
                <group>
                    <group string="Warranty" id="warranty-left">
                        <label name="warranty" for="warranty"/>
                        <div>
                            <field name="warranty" class="oe_inline"/>
                            <field name="warranty_type" class="oe_inline"/>
                        </div>
                    </group>
                    <group id="warranty-right"/>
                </group>
            </page>
        </field>
    </record>

</odoo>