Vocal is related to Mouth. Mouth is a different concept from Ear. Ear is related to Shell. Shell is related to Inside. 
Like is related to Look. Look is a synonym of Investigate. Explore is a type of Investigate. Pioneer is a type of Explore. 
Vocal <--RelatedTo--> Mouth <--DistinctFrom--> Ear <--RelatedTo--> Shell <--RelatedTo--> Inside 
Like <--RelatedTo--> Look <--Synonym--> Investigate <--IsA-- Explore <--IsA-- Pioneer 