src/lib/models/delivery.php

<?php
class delivery extends \Phalcon\Mvc\Model
{
    public function getDistinct($data,$name,$modelsManager, $project_id){
        $sql = "SELECT DISTINCT {$data} FROM delivery WHERE {$data} LIKE '%$name%' AND project_id = {$project_id}";
        return $modelsManager->createQuery($sql)->execute()->toArray();
    }
}