public function request($params)
  {
    $query = array_merge($params, [
      'key' => $this->key
    ]);

    try {

      $response = $this->client->get(self::API_ENDPOINT, [
        'query' => $query
      ]);

    } catch (ClientException $exception) {

      return collect([]);

    }

    $results = json_decode($response->getBody(), true);

    $output = [];

    for($i = 0; $i < count($results['itemListElement']); $i++) {
      $output[] = new SearchResult($results['itemListElement'][$i]);
    }

    return collect($output);
  }