string(256) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%85%B3%E9%94%AE%E8%AF%8D%E6%8E%92%E5%90%8D%E8%BD%AF%E4%BB%B6%E6%9C%89%E7%94%A8%E5%90%97 => Failed to connect to 218.78.59.96 port 38042: Connection refused"
关键词排名软件有用吗
