string(275) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%B6%88%E9%98%B2%E5%B7%A5%E7%A8%8B%E5%B8%88%E6%95%99%E6%9D%902020%E5%92%8C2021%E7%9A%84%E5%8C%BA%E5%88%AB => Failed to connect to 101.89.159.206 port 38075: Connection refused"
消防工程师教材2020和2021的区别
