string(256) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%BA%8C%E5%BB%BA%E5%A4%87%E8%80%83%E9%9C%80%E8%A6%81%E7%9C%8B%E6%95%99%E6%9D%90%E5%90%97 => Failed to connect to 14.18.117.71 port 38041: Connection refused"
二建备考需要看教材吗
