string(292) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%AE%80%E8%BF%B0%E7%BD%91%E7%BB%9C%E4%BF%83%E9%94%80%E4%B8%8E%E4%BC%A0%E7%BB%9F%E4%BF%83%E9%94%80%E7%9A%84%E5%8C%BA%E5%88%AB => Failed to connect to 61.171.74.35 port 38041: Connection refused"
简述网络促销与传统促销的区别
