Glue is the substance that holds things together, and substance is the thing that makes hub scores rise (as well as time).
So, do you go out and buy glue? Nope, but adding more substance to your hubs would be a good step forward. As a rule hubs should be between 500 and 1500 words, though you should by all means write more if a topic needs better explaining.
One paragraph in a book does little to tell a story, just as one paragraph in a hub does little to cover the topic at hand. For that reason, your hub score will rise slowly, or might not rise at all.
By writing longer and more informative hubs I think you will find your hubscore rising, and withing a week you should be able to break a score of at least 50.
So, lengthen your hubs with good content and I think you will do just fine.
I Hope this helps! :)