用elasticsearch-phplaravel为什么不能返回高亮数据？

<code>    namespace App\Http\Controllers\Search;
    use Illuminate\Http\Request;
    use App\Http\Requests;
    use App\Http\Controllers\Controller;
    use Elasticsearch\Client;
class Index extends Controller
{
    protected $client;
    public function __construct(Client $client)
    {
        $this->client = $client;
    }
    public function search_test(Request $request,$filter='list'){
        $word = trim($request->input('word'));
        $s=is_null($request->input('s'))?10:trim($request->input('s'));//一页多少条
        $f=is_null($request->input('f'))?1:trim($request->input('f'));//当前页数
        $fr=($f-1)*$s;//当前页从第一条记录开始
        $params=[
            'index' => 's_index',
            'type' => 's_type',
            'body' => [
                'query' => [
                    'bool' => [
                        'should' => [
                            [ 'match' => [ 'title' => $word ] ],
                            [ 'match' => [ 'description' => $word ] ],
                        ]
                    ]
                ]
                ,'from'=>$fr, 'size'=>$s
                ,'highlight'=>[
                    'fields'=>[
                        'title'=>[]
                    ]
                ]
            ]
        ];
        $response = $this->client->search($params);
        echo "<pre class="brush:php;toolbar:false layui-box layui-code-view layui-code-notepad"><ol class="layui-code-ol"><li>";</li><li>        var_dump($response);</li><li>        echo "</li></ol></pre>";
    } 
} </code>

查询结果都能返回，就是无highlight数据，求朋友帮忙！！！

回复内容：

<code>    namespace App\Http\Controllers\Search;
    use Illuminate\Http\Request;
    use App\Http\Requests;
    use App\Http\Controllers\Controller;
    use Elasticsearch\Client;
class Index extends Controller
{
    protected $client;
    public function __construct(Client $client)
    {
        $this->client = $client;
    }
    public function search_test(Request $request,$filter='list'){
        $word = trim($request->input('word'));
        $s=is_null($request->input('s'))?10:trim($request->input('s'));//一页多少条
        $f=is_null($request->input('f'))?1:trim($request->input('f'));//当前页数
        $fr=($f-1)*$s;//当前页从第一条记录开始
        $params=[
            'index' => 's_index',
            'type' => 's_type',
            'body' => [
                'query' => [
                    'bool' => [
                        'should' => [
                            [ 'match' => [ 'title' => $word ] ],
                            [ 'match' => [ 'description' => $word ] ],
                        ]
                    ]
                ]
                ,'from'=>$fr, 'size'=>$s
                ,'highlight'=>[
                    'fields'=>[
                        'title'=>[]
                    ]
                ]
            ]
        ];
        $response = $this->client->search($params);
        echo "<pre class="brush:php;toolbar:false layui-box layui-code-view layui-code-notepad"><ol class="layui-code-ol"><li>";</li><li>        var_dump($response);</li><li>        echo "</li></ol></pre>";
    } 
} </code>

查询结果都能返回，就是无highlight数据，求朋友帮忙！！！

暂时没做过搜索服务，感觉高亮的数据应该在控制器里面处理的吧。