Relevant is related to Current. Current is related to Pulse. Impulse is etymologically related to Pulse. 
Vacation is related to Term. Term is related to Correspondent. Correspondent is related to Person. Ethnic is a type of Person. 
Relevant <--RelatedTo--> Current <--RelatedTo--> Pulse <--EtymologicallyRelatedTo-- Impulse 
Vacation <--RelatedTo--> Term <--RelatedTo--> Correspondent <--RelatedTo--> Person <--IsA-- Ethnic 