string(276) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E8%A7%86%E9%A2%91%E6%B8%B2%E6%9F%93%E7%9A%84%E4%BD%9C%E7%94%A8%E6%98%AF%E4%BB%80%E4%B9%88%E5%8E%9F%E7%90%86 => Failed to connect to 101.89.117.144 port 38208: Connection refused"
视频渲染的作用是什么原理
