string(265) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%9C%89%E5%A4%9A%E5%B0%91%E4%BD%8D%E7%BE%8E%E5%9B%BD%E6%80%BB%E7%BB%9F%E8%A2%AB%E5%88%BA%E6%9D%80 => Failed to connect to 14.18.117.71 port 38041: Connection refused"
有多少位美国总统被刺杀
