Water can be used for Drinking. Drinking can cause/lead to Swallow. Swallow is related to Body. Body is related to Being. 
Search is a type of Examination. Examination is related to Observation. Observation is related to Tower. 
Water --UsedFor--> Drinking --Causes--> Swallow <--RelatedTo--> Body <--RelatedTo--> Being 
Search --IsA--> Examination <--RelatedTo--> Observation <--RelatedTo--> Tower 