string(275) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=2021%E4%BA%8C%E5%BB%BA%E8%80%83%E8%AF%95%E8%A6%81%E7%9C%8B2021%E5%B9%B4%E7%9A%84%E6%95%99%E6%9D%90%E5%90%97 => Failed to connect to 101.89.117.144 port 38208: Connection refused"
2021二建考试要看2021年的教材吗
