string(231) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%B1%BD%E6%9C%BAeh%E6%B2%B9%E7%B3%BB%E7%BB%9F%E4%BD%9C%E7%94%A8 => Failed to connect to 14.18.117.71 port 38133: Connection refused"
汽机eh油系统作用
