string(256) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E9%95%BF%E5%B0%BE%E5%85%B3%E9%94%AE%E8%AF%8D%E6%8C%96%E6%8E%98%E6%9C%BA%E7%BD%91%E7%AB%99 => Failed to connect to 61.171.74.35 port 38027: Connection refused"
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