string(256) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%94%B6%E9%9B%86%E5%A4%A7%E6%95%B0%E6%8D%AE%E6%9C%89%E4%BB%80%E4%B9%88%E7%94%A8%E9%80%94 => Failed to connect to 14.18.117.71 port 38164: Connection refused"
收集大数据有什么用途
