string(264) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%B8%80%E5%BB%BA%E6%9C%BA%E7%94%B5%E8%AF%BE%E6%9C%AC%E4%BE%8B%E9%A2%98%E5%87%BA%E9%A2%98%E7%8E%87 => Failed to connect to 14.18.46.51 port 38044: Connection refused"
一建机电课本例题出题率
