Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Aug. 31, 2017	Aug. 31, 2016
Cash flows from operating activities:
Consolidated net income	$ 160,359	$ 155,919
Adjustments to reconcile consolidated net income to net cash provided by operating activities:
Depreciation and amortization	4,210	5,359
Unrealized loss (gain) on marketable securities, net	832	(3,440)
Deferred income taxes	(6,000)	6,000
Changes in operating assets and liabilities:
Accounts receivable	(159,863)	(116,476)
Other receivables	14,148	(3,263)
Prepaid expenses	66,601	(78,608)
Prepaid and recoverable income taxes	94,833
Accounts and other payables and accrued expenses and other current liabilities	510,991	(16,483)
Income taxes payable	23,793	60,921
Advances from customers	(156,882)	18,290
Net cash provided by operating activities	553,022	28,219
Cash flows from investing activities:
Proceeds from maturities of marketable securities	248,000	248,000
Purchases of marketable securities		(249,000)
Net cash provided by (used in) investing activities	248,000	(1,000)
Cash flows from financing activities:
Cash dividend paid	(1,962,062)
Distribution to noncontrolling interest	(4,350)	(4,650)
Net cash used in financing activities	(1,966,412)	(4,650)
Net increase (decrease) in cash and cash equivalents	(1,165,390)	22,569
Cash and cash equivalents at beginning of period	5,723,976	4,514,157
Cash and cash equivalents at end of period	4,558,586	4,536,726
Supplemental disclosures of cash flow data:
Income taxes paid	$ 5,000	$ 69,000