It may be that your feed settings are set to view only those friends and pages you interact with regularly. If you don’t like that then here’s the right way to alter what posts to see in facebook.
From your News Feed page click the Most Recent drop-down menu (This may be called Status Updates or a number of other things, whatever, just click it to open the menu)
At the bottom of the drop-down menu click Edit Options
From the window that pops up, click the drop-down menu next to Show posts from
Now, simply click Save and you’re done.
Hope that clears up a few things for folk.