string(265) "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%E5%BC%95%E7%94%A8%E6%A0%87%E6%B3%A8%E7%9A%84%E6%AD%A3%E7%A1%AE%E6%A0%BC%E5%BC%8F => Failed to connect to 14.18.117.71 port 38093: Connection refused"
论文引用标注的正确格式
