I want to get face photos or images of a given race e.g. asians from search engines like google.com or bing.com for a photo profiling software project I am building. What would be the best search text or string that I would issue to a search engine to get face photos in their thousands? Is there a research database instead that is available for downloading photos or images e.g. categorized by race e.g asians database, africans etc?

I will gladly appreciate your help and suggestions on this.