A while back I was talking with a friend about how God promises to give us the desires of our heart. Her desire was to have a baby girl (she was blessed with a boy instead). My desire is to get pregnant (I have been blessed with time to draw closer to God and wait on His perfect timing instead). I think that sometimes we read that verse and automatically think on the desires of our flesh rather than what our heart and soul actually desire. I think what God is promising is that He will satisfy us completely if we just set our hearts on Him.
Matthew 6:21 For where your treasure is, there your heart will be also.