Smell is related to Touch. Touch is related to Sensation. Smooth is a type of Sensation. Smooth is related to Seal. 
Harsh is a synonym of Hard. Hard is related to Difficulty. Fix is a type of Difficulty. Fix is related to Design. 
Smell <--RelatedTo--> Touch <--RelatedTo--> Sensation <--IsA-- Smooth <--RelatedTo--> Seal 
Harsh <--Synonym--> Hard <--RelatedTo--> Difficulty <--IsA-- Fix <--RelatedTo--> Design 