string(231) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%8D%81%E4%BA%8C%E6%9D%A1%E5%89%8D%E6%8F%90%E5%81%87%E8%AE%BE => Failed to connect to 101.89.117.144 port 38208: Connection refused"
十二条前提假设
