string(265) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%88%86%E5%88%AB%E7%94%A8%E4%B8%A4%E7%BB%84%E4%B8%8D%E5%90%8C%E7%9A%84%E5%85%B3%E8%81%94%E8%AF%8D => Failed to connect to 14.18.117.71 port 38069: Connection refused"
分别用两组不同的关联词
