string(275) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=2021%E5%B9%B4%E4%B8%80%E5%BB%BA%E6%95%99%E6%9D%90%E5%92%8C2020%E7%9A%84%E6%9C%89%E5%B7%AE%E5%88%AB%E5%90%97 => Failed to connect to 125.88.227.171 port 38062: Connection refused"
2021年一建教材和2020的有差别吗
