You need to get into the minds of your subscribers, post the kind of content that they want to see. See how your competitors are doing it. What kind of posts are they posting, which ones are most popular and why. Try to post same kind of stuff in your page, and if possible go one step further and make it even better.
Post the kind of stuff that people would like to share with others. The more your content is shared, the higher reach you're going to be getting.