string(265) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%BD%91%E7%BB%9C%E6%8E%A8%E5%B9%BF%E6%9C%89%E5%93%AA%E5%87%A0%E7%A7%8D%E6%96%B9%E6%B3%95%E5%91%A2 => Failed to connect to 14.18.117.71 port 38220: Connection refused"
网络推广有哪几种方法呢
