string(260) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=2020%E5%B9%B4%E4%BA%8C%E5%BB%BA%E6%9C%BA%E7%94%B5%E7%9F%A5%E8%AF%86%E7%82%B9%E6%80%BB%E7%BB%93 => Failed to connect to 14.18.117.71 port 38069: Connection refused"
2020年二建机电知识点总结
