Note 3 - Summary of Significant Accounting Policies - Exchange Rates Used to Translate Amounts In RMB Into US$ (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Balance sheet items, except for equity accounts	6.5249	6.9762
Items in the statements of operations and comprehensive loss	6.8976	6.8985

Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6450520&loc=d3e32618-110901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant