string(238) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E9%9D%A2%E8%AF%95%E5%B8%B8%E9%97%AE%E5%88%B0%E7%9A%84%E9%97%AE%E9%A2%98 => Failed to connect to 14.116.215.7 port 38230: Connection refused"
面试常问到的问题
