rma/crm_rma_stock_location/views/product_product.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <record id="rma_product_product_tree_view" model="ir.ui.view">
        <field name="name">product.stock.tree.inherit</field>
        <field name="model">product.product</field>
        <field name="arch" type="xml">
            <tree string="Product Variants" create="false">
                <field name="default_code"/>
                <field name="name"/>
                <field name="attribute_value_ids" widget="many2many_tags"/>
                <field name="rma_qty_available"/>
                <field name="rma_virtual_available"/>
            </tree>
        </field>
    </record>

    <record id="rma_product_search_view" model="ir.ui.view">
        <field name="name">product.product.search</field>
        <field name="model">product.product</field>
        <field name="arch" type="xml">
            <search string="RMA Products">
                <separator/>
                <filter name="rma_available" string="RMA Available Products"
                    domain="['|', ('rma_qty_available','&gt;',0), ('rma_virtual_available','&gt;',0)]"/>
            </search>
        </field>
    </record>

    <record id="rma_product_variant_action" model="ir.actions.act_window">
        <field name="name">RMA Stock</field>
        <field name="type">ir.actions.act_window</field>
        <field name="res_model">product.product</field>
        <field name="view_mode">tree</field>
        <field name="view_type">form</field>
        <field name="view_id" ref="rma_product_product_tree_view"/>
        <field name="search_view_id" ref="rma_product_search_view"/>
        <field name="context">{'search_default_rma_available': 1}</field>
    </record>

    <menuitem action="rma_product_variant_action"
        id="menu_stock_rma" parent="base.menu_aftersale"
        name="RMA Stock"
        sequence="100"/>
</odoo>