public function suggest($suggester, $options = [])
    {
        if (empty($suggester)) {
            $suggester = '{}';
        }
        if (is_array($suggester)) {
            $suggester = Json::encode($suggester);
        }
        $url = [
            $this->index !== null ? $this->index : '_all',
            '_suggest'
        ];

        return $this->db->post($url, array_merge($this->options, $options), $suggester);
    }