string(258) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=21%E6%9D%A1%E6%98%AF%E5%93%AA%E4%B8%80%E5%B9%B4%E7%AD%BE%E8%AE%A2%E7%9A%84%E5%8D%8F%E8%AE%AE => Failed to connect to 14.18.117.71 port 38093: Connection refused"
21条是哪一年签订的协议
