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Schedule of Other Current Assets (Details) - USD ($) $ in Thousands | Jul. 31, 2021 | Apr. 30, 2021
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Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] |  |
Deposits | $ 70 | $ 68
Other receivables | 17 | 21
Prepaid insurance | 97 | 194
Prepaid recruiting | 148 | 12
Prepaid expenses- other | 175 | 192
Other current assets | $ 507 | $ 487

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