string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%9F%AD%E8%B7%AF%E5%92%8C%E6%96%AD%E8%B7%AF%E7%9A%84%E8%A1%A8%E7%8E%B0 => Failed to connect to 101.89.143.195 port 38175: Connection refused"
短路和断路的表现
