Only believe
Words carry power but when belief is mixed with your words,you see the manifested result of your prayer.Could it be at times ,it's not that God has denied us or delayed us but that we simply don't believe ?
You see Jesus knew our struggle with belief as mankind that's why he mentioned BELIEF/BELIEVING so many times in the bible.I believe if Adam and Eve truly believed what God said they wouldn't have eaten from the forbidden tree,so chances are we are still suffering from the side effects of what happened in the garden of Eden.I also believe that strong belief comes via imagination,when you imagine or picture the manifest result of your prayer,that seals the deal.
Shalom and love