string(294) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%94%9F%E7%B2%89%E5%92%8C%E6%B0%B4%E6%B7%80%E7%B2%89%E6%98%AF%E4%B8%80%E6%A0%B7%E5%8F%AF%E4%BB%A5%E5%8B%BE%E8%8A%A1%E5%90%97 => Failed to connect to 101.89.117.144 port 38056: Connection refused"
生粉和水淀粉是一样可以勾芡吗
