string(274) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%BA%8C%E5%BB%BA%E5%BB%BA%E7%AD%91%E4%B8%8E%E6%9C%BA%E7%94%B5%E6%95%99%E6%9D%90%E7%9A%84%E5%8C%BA%E5%88%AB => Failed to connect to 14.18.117.71 port 38164: Connection refused"
二建建筑与机电教材的区别
