Stimulus is a synonym of Impulse. Impulse is a synonym of Urge. Urge is related to Want. Want is a synonym of Search. 
Perfect is related to Right. Right is related to Answer. 
Stimulus <--Synonym--> Impulse <--Synonym--> Urge <--RelatedTo--> Want <--Synonym--> Search 
Perfect <--RelatedTo--> Right <--RelatedTo--> Answer 