Retail is related to Sale. Solar is etymologically related to Sale. 
Discussion is related to Committee. Committee is related to Organization. Organization is a type of Administration. Administration is a type of Management. 
Retail <--RelatedTo--> Sale <--EtymologicallyRelatedTo-- Solar 
Discussion <--RelatedTo--> Committee <--RelatedTo--> Organization --IsA--> Administration --IsA--> Management 