string(256) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%A6%82%E4%BD%95%E6%8F%90%E9%AB%98%E6%90%9C%E7%B4%A2%E7%9A%84%E5%87%86%E7%A1%AE%E7%8E%87 => Failed to connect to 14.18.117.71 port 38041: Connection refused"
如何提高搜索的准确率
