Hello Zinedine Kahlil Gibran Zidane,

Please try below code it will help you

class ResPartner(models.Model):
_inherit = "res.partner"

partner_type = fields.Selection([('vendor', 'Vendor')], string='Partner type')


@api.model
def search_read(self, domain=None, fields=None, offset=0, limit=None, order=None):
if self.env.user.has_group('sales_team.group_sale_salesman') and \
not self.env.user.has_group('sales_team.group_sale_manager') and \
not self.env.user.has_group('sales_team.group_sale_salesman_all_leads'):
domain += [('partner_type', '=','vendor')]
return super(ResPartner, self).search_read(domain=domain, fields=fields, offset=offset, limit=limit, order=order)

Thanks & Regards,
Email: odoo@aktivsoftware.com
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