string(274) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E8%BA%AB%E8%BE%B9%E6%9C%89%E5%93%AA%E4%BA%9B%E6%9C%89%E8%B6%A3%E7%9A%84%E7%89%A9%E7%90%86%E7%8E%B0%E8%B1%A1 => Failed to connect to 14.18.117.71 port 38093: Connection refused"
身边有哪些有趣的物理现象
