themes of the story (I'm not satisfied with this word) topics of the story (what it is about, several items/points) message(s) of the story (what you want to tell /to express) (but you already wrote 'message' later in the sentence)

I read this sentence in two ways - With 1 main theme of Personal Responsibility (personal responsibility TO help others and cooperate with them). In this case I would use the singular for "theme" and a semi-colon - The theme of the story is personal responsibility; using One's abilities to cooperate with, and help others. There is therefore a hidden message within the story's context. (or within the context of the story). - With 3 seperate themes - PR, helping others AND cooperation (although we can put the last two together. In this case I would use the plural like you have - The themes of the story are personal responsibility and the importance of helping others and cooperation. There is therefore a moral behind the story....[explain what it has shown you eg. ...story which is that through helping others, we can also help ourselves]. The word "themes" is correct. It means the same as topic/subject/what the story is about. It is a good word to use!

"themes".. hm. Probably "The story tells us about..." and almost every other variant from previous answer are better, IMHO. and the words responsibility and ability don't look nice (esp. here, standing one-by-one)