Cash and Cash Equivalents (Details) - Schedule of cash and cash equivalents - USD ($)	Feb. 28, 2021	May 31, 2020	Feb. 29, 2020	May 31, 2019
Schedule of cash and cash equivalents [Abstract]
Cash in banks	$ 6,580,695	$ 9,677,848
Money market funds	52,850	52,174
Total	$ 6,633,545	$ 9,730,022	$ 3,473,282	$ 3,694,989

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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