Note 10 - Major Customer and Vendor (Details)	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Number Of Major Distributors	The Company sold products mostly through ten distributors	The Company sold products mostly through ten distributors
Concentration Risk, Other Risk	Sales to five distributors represented 15%, 14%, 12%, 11%, and 11% of total sales	sales to five distributors represented 17%, 14%, 12%, 11%, and 11% of total sales	sales through six distributors represented 16%, 14%, 12%, 11%, 11%, and 10% of total sales	Sales to four distributors represented 17%, 16%, 13%, and 12% of total sales
Concentration Risk, Product	Sales of three products represented 37%, 22%, and 11% of total sales	Sales of two products represented 38% and 24% of total sales	Sales of three products represented 37%, 24%, and 12% of total sales	Sales of three products represented 41%, 17% and 10% of total sales
Shandong Yongchuntang
Concentration Risk, Supplier	36%	33%	38%	42%
Other Vendor 1
Concentration Risk, Supplier	31%	33%	28%	25%
Other Vendor 2
Concentration Risk, Supplier	13%	13%	12%	14%
Other Vendor 3
Concentration Risk, Supplier	10%	11%	11%