string(276) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%91%98%E8%A6%81%E8%AE%BA%E6%96%87%E6%A0%BC%E5%BC%8F%E5%AD%97%E4%BD%93%E5%AD%97%E5%8F%B7%E8%A6%81%E6%B1%82 => Failed to connect to 101.89.159.206 port 38087: Connection refused"
摘要论文格式字体字号要求
