string(274) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%BA%8C%E5%BB%BA%E6%95%99%E6%9D%902021%E7%94%B5%E5%AD%90%E7%89%88pdf%E5%85%8D%E8%B4%B9%E4%B8%8B%E8%BD%BD => Failed to connect to 101.89.166.210 port 38089: Connection refused"
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