Visit the non-profit company's website. Many non-profit companies will post their mission, leadership, and financial information on their website.
Look for news about your company. News stories can provide insight into what your company is actually doing to fulfill their mission.
Search for your company using the resources in the Company Data tab. Research is about trial and error, so don't give up if you don't find much on your first attempt.
GuideStar USA, Inc. is an information service specializing in reporting on U.S. nonprofit companies. In 2016, its database provided information on 2.5 million organizations.