string(261) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=etf%E6%8A%98%E4%BB%B7%E7%8E%87%E5%92%8C%E6%BA%A2%E4%BB%B7%E7%8E%87%E4%B8%80%E6%A0%B7%E5%90%97 => Failed to connect to 101.89.117.144 port 38017: Connection refused"
etf折价率和溢价率一样吗
