string(271) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=2021%E4%BA%8C%E5%BB%BA%E6%B0%B4%E5%88%A9%E5%AE%9E%E5%8A%A1%E6%A1%88%E4%BE%8B%E9%A2%98%E8%AE%B2%E8%A7%A3 => Failed to connect to 101.89.117.144 port 38022: Connection refused"
2021二建水利实务案例题讲解
