There isn't really a book that will teach you how to stop taking things literally. You have to work on your third eye and upper chakras to improve your ability to sense hidden meanings.
Another thing you should do is read works that interpret allegories, like JOS sermons and the works of Jung. Some astrologers also go into the symbolism of mythology.
You just need to read things that help you understand how a hidden meaning can present itself and train your mind to look for it. Ask yourself, since you know the story isn't literal, what the story could mean and really try to break it down and see what its true meaning is. This will help you train your mind.