string(306) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%8D%A2%E6%89%8B%E7%8E%87%E9%AB%98%E4%B8%80%E8%88%AC%E8%AF%B4%E6%98%8E%E4%BB%80%E4%B9%88%2C%E5%A4%9A%E5%B0%91%E6%89%8D%E7%AE%97%E9%AB%98 => Failed to connect to 125.88.227.171 port 38062: Connection refused"
换手率高一般说明什么,多少才算高
