string(264) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E8%AE%BA%E6%96%87%E6%91%98%E8%A6%81%E4%B8%80%E8%88%AC%E6%80%8E%E4%B9%88%E5%86%99%E5%A5%BD%E5%91%A2 => Failed to connect to 14.18.46.51 port 38044: Connection refused"
论文摘要一般怎么写好呢
