Person wants (to) Mobile. you are likely to find Blood in/at/on Person. Blood is related to Oil. Oil is related to Part. 
Subject is related to Card. Card is related to Element. Element is related to Letter. Letter is related to Envelope. 
Mobile <--Desires-- Person <--AtLocation-- Blood <--RelatedTo--> Oil <--RelatedTo--> Part 
Subject <--RelatedTo--> Card <--RelatedTo--> Element <--RelatedTo--> Letter <--RelatedTo--> Envelope 