CakePHP 3.6：带条件的fetchAll（）

I would like to add search functionality in my view. The problem is that I get data from raw sql like this so I dont know how to filter the results:

        $conn = ConnectionManager::get('default');
        $stmt = $conn->execute('SELECT c.id as customerid, CONCAT(c.name, " ", c.surname) as customer, s.title as title, s.length, cs.created , DATE_ADD(cs.created, INTERVAL s.length DAY) as expiring_date, DATEDIFF(DATE_ADD(cs.created, INTERVAL s.length DAY), NOW()) as days_left
                                FROM customers c 
                                JOIN customer_service_types cs on c.id = cs.customer_id
                                JOIN service_types s on cs.service_type_id = s.id
                                WHERE s.is_subscription = 1 and DATE_ADD(cs.created, INTERVAL s.length DAY) > DATE_ADD(NOW(), INTERVAL -30 DAY)
                                ORDER BY expiring_date');
        $expiringServices = $stmt->fetchAll('assoc');
        //debug($expiringServices,true);

        $this->set(compact('expiringServices'));

Is it possible to filter the results by a form input? I want the user to filter the results by entering the name in a text field and compare it with customer field which returns from the sql query. One guess is the fetchAll(PDO::FETCH_FUNC, fun_name) but I dont know how to implement it.