string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%9B%AE%E6%A0%87%E7%BE%A4%E4%BD%93%E5%88%92%E5%88%86%E6%A0%87%E5%87%86 => Failed to connect to 101.89.159.206 port 38075: Connection refused"
目标群体划分标准
