public function get($label = null)
    {
        if ($label && array_key_exists($label, $this->results)) {
            return $this->results[$label];
        }
        $results = [];
        foreach ($this->results as $v) {
            if (is_array($v)) {
                $results = array_merge($results, $v);
            } else {
                $results[] = $v;
            }
        }

        return $results;
    }