string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%B8%A6%E5%AE%BD%E4%B8%8E%E9%80%9F%E7%8E%87%E7%9A%84%E5%85%B3%E7%B3%BB => Failed to connect to 101.89.159.206 port 38075: Connection refused"
带宽与速率的关系
