string(260) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=dy%E6%98%AF%E4%BB%80%E4%B9%88%E6%84%8F%E6%80%9D%E6%95%B0%E5%AD%A6%E6%80%8E%E4%B9%88%E6%B1%82 => Failed to connect to 125.88.227.171 port 38062: Connection refused"
dy是什么意思数学怎么求
