I'm not sure if I got the question right. There is quite a number of nutraceuticals from Chinese medicine, for instance, which act as nootropic agents; I think you might refer to synthetic drugs. As to these, I have no reliable data on usage in different countries and especially not in eastern countries; but it might be that "traditional" remedies are considered better.
Eastern country believes in yoga, herbs, and diet style, spirituality, meditation and alternative therapies like acupressure, acupuncture etc., This may be the reason that eastern countries does not trust nootropic agents for the treatment of behavior.