Odoo specific form view on many2many field

I have many2many field:

supply_ids = fields.Many2many(comodel_name='supply.conditions',
                                          relation='purchase_supply_rel',
                                          column1='purchase_requests_id', column2='supply_conditions_id',
                                          string='Supply Conditions')

and piece of xml

 <page string="Order">
        <field name="supply_ids"/>
 </page>

I have only one supply.conditions form view but I want create another one (with less fields) and show it on supply_ids field click:

"Add object" -> "Create"

I don't know what method is called on "Add object" click or how can I select specific form view on "Add object" -> "Create" button..