string(241) "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%E4%B9%A6%E7%B1%8Dpdf%E4%B8%8B%E8%BD%BD%E5%85%8D%E8%B4%B9 => Failed to connect to 61.171.74.35 port 38041: Connection refused"
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