Note 6 - Related Party Transactions (Details) - USD ($)	3 Months Ended		9 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2018	Jan. 31, 2017	Apr. 30, 2017
Details
Accounts receivable - related party Qufu Shengwang	$ 2,479,670		$ 2,479,670		$ 339,270
Revenue - related party Qufu Shengwang	1,591,329	$ 2,129,371	1,858,709	$ 5,591,740
Advances from related parties for working capital			5,068,601	2,595,313
Repaid to related parties for working capital			3,251,990	2,768,284
Interest expense related to due to related parties	$ 25,945	$ 38,207	$ 71,135	$ 96,320