odoo_top_trending_products/views/product_view.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <record id="product_template_search_view_top25_product" model="ir.ui.view">
            <field name="name">product.template.filter</field>
            <field name="model">product.template</field>
            <field name="inherit_id" ref="product.product_template_search_view"/>
            <field name="arch" type="xml">
                <xpath expr="//search" position="inside">
                    <separator/>
                    <filter string="Top productos más vendidos" domain="[('id','!=',False)]" context="{'top_25': True}" />
                    <separator/>
                    <filter string="Top productos más comprados" domain="[('id', '!=', -1)]" context="{'top_25': True}" />
                </xpath>
            </field>
        </record>
    </data>
</openerp>