Hi,
You can put the following code in your xml file:
<record id="multiprice_search_form_view_inherited" model="ir.ui.view">
<field name="name">multiprice.search.form.inherited</field>
<field name="model">product.template</field>
<field name="inherit_id" ref="product_multiprices.multiprice_search_form_view"/>
<field name="arch" type="xml">
<field name="name" position="after">
<field name="name" string="Your Search Term" filter_domain="[('your_field','ilike',self)]"/>
</field>
</field>
</record>
Here, your_field is the field you added in product.template model. Then it should appear in "Search more" as you expected in quotation or sale order lines
If you want to do this from front end, you may do the following:
Create a new view with following data and rest keep as default:
View Name: product.template.search.inherited
View Type: Search
Object: product.template
Inherited View: product.template.search
View inheritance mode: Extension View
Then under Architecture tab, put the following code:
<?xml version="1.0"?>
<field name="name" position="after">
<field name="name" string="Your Search Term" filter_domain="[('your_field','ilike',self)]"/>
</field>