string(238) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%B8%93%E9%97%A8%E4%B9%B0%E5%9B%BE%E4%B9%A6%E7%9A%84%E7%BD%91%E7%AB%99 => Failed to connect to 14.18.117.71 port 38069: Connection refused"
专门买图书的网站
