Obtain is related to Buy. Buy is related to Acquire. Acquire is a synonym of Secure. Secure is similar to Tight. 
Earth is related to Atmosphere. you are likely to find Storm in/at/on Atmosphere. Storm is a synonym of Surprise. Surprise is related to Related. 
Obtain <--RelatedTo--> Buy <--RelatedTo--> Acquire <--Synonym--> Secure <--SimilarTo--> Tight 
Earth <--RelatedTo--> Atmosphere <--AtLocation-- Storm <--Synonym--> Surprise <--RelatedTo--> Related 