ne pas utiliser un champ calculé non stocké dans un domaine de recherche :

payment_state=fields.Selection(string='payment_state',selection=[('paid', 'paid'), ('not paid', 'not paid')],compute='_compute_payment_state',store=True)

member=self.env['kalachakra.membership'].search([('partner_id','=', int(self.partner_id)),('end_date','>=',datetime.now()),('payment_state','=','paid')])