string(301) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%BA%8C%E7%BA%A7%E5%BB%BA%E9%80%A0%E5%B8%88%E6%9C%BA%E7%94%B5%E5%B7%A5%E7%A8%8B%E8%80%83%E4%BB%80%E4%B9%88%E5%86%85%E5%AE%B9%E5%95%8A => Failed to connect to 61.171.74.35 port 38027: Connection refused"
二级建造师机电工程考什么内容啊
