Research is a synonym of Examination. Oral is a type of Examination. Oral is related to Testimony. Testimony is related to Written. 
Tale is a synonym of Legend. you are likely to find Legend in/at/on Map. Map is related to Point. 
Research <--Synonym--> Examination <--IsA-- Oral <--RelatedTo--> Testimony <--RelatedTo--> Written 
Tale <--Synonym--> Legend --AtLocation--> Map <--RelatedTo--> Point 