string(293) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%BD%91%E9%A1%B5%E4%B8%AD%E7%9A%84%E5%85%B3%E9%94%AE%E8%AF%8D%E8%AF%A5%E5%A6%82%E4%BD%95%E4%BC%98%E5%8C%96%E6%89%8D%E7%AE%97%E5%90%88%E7%90%86 => Received HTTP code 403 from proxy after CONNECT"
网页中的关键词该如何优化才算合理
