string(249) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=21%E4%B8%96%E7%BA%AA%E6%95%99%E8%82%B2%E7%BD%91%E5%85%8D%E8%B4%B9%E7%AD%94%E6%A1%88 => Failed to connect to 14.18.117.71 port 38220: Connection refused"
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