As time passed by I realized that sharing is caring (as Vinicius Nobre said at the TDC Plus). Do it because you want to, because you care and you surely will be able to create a better place to work. Where I work, I don´t have this kind of problem, because sharing is only natural. I fell safe and comfortable about what I am doing because my co-workers are reliable.
We all get along because we respect each other and we multiply our knowledge about how to teach, or how to deal with some kind of situation. It is a place where I feel safe, because I know I can count on people, on my boss, or whoever I need.
So if I can give you any advice, don´t be afraid of sharing information, you will only be helping each other to multiply the feeling of care around yourselves. Getting along with people you work with makes your life easier, and dividing experiences help others to create knowledge.