The following commentary is not endorsed by either the Oswald Chambers Society or the publisher.  These insights have been delivered through 808. 

"You ask and do not receive because you ask amiss."  "B U T!" you cry,  "I am only asking God to heal a friend or to give someone safety in travel or to help a student do well on an exam."  What could be amiss about that?  Well here is the answer to that question.  These requests are all of a selfish nature.  These are all to the end that someone will be relieved of discomfort or anxiety.  And that is contrary to the WILL OF GOD.  "How so," you ask.  In this way:  God's blessing is neither material properity nor life without turmoil.  God's blessing is that we KNOW BEYOND THE SLIGHTEST DOUBT that God has brought these circumstances to bear to bring each person to the point where they are willing to TRUST GOD completely, rather than their own abilities.  

God is not a lucky charm.  He will actually resist your prayer whenever its focus is not completely and utterly on each prayer's object finding greater intimacy through greater surrender.  I do not need to ask God for safety in travel.  His will is that, regardless of the nature of the journey, I am confident that harm will not come to me unless He will receive a greater glory through it.  If He will get greater glory in my harm, then I welcome such harm as a wonderful gift from God.  Then I am actually a participant in the blessing and glory of God.  God would rather I be heroic than unharmed.  Heroes are those who either sacrifice their lives for others or save another through some life threatening action.  If we are willing to be heroes for God's glory always, we will be blessed beyond our wildest imaginations.

Examine your prayers.  Examine every one of them.  Remove any requests from your prayer list which are NOT centered on that person's greater intimacy with God, but rather on that person's relief from whatever is "troubling" them.  If we ask God to heal someone, whose healing will hinder another from receiving God's salvation, He is not likely to answer that prayer with a "yes."  Further, in order to not pray "amiss," we must think like God thinks, in the eternal realm.  So consider, too, whether your prayer's answer has any eternal value.  If the request is not about an eternally valuable result, strike it from your list.  My list was almost entirely erradicated when I took stock in this way.

Even our Lord's Prayer was all about "Our heavenly Father's incredible value, His kingdom's expansion, His will's happening on the human plane, our "needs" satisfied, but no mention of our "wants", forgiveness all around (mine and yours), our affection for God leading us away from our selfishness at all levels, our deliverance from selfish actions and attitudes, God's kingdom, power, and glory only ever and always!  The focus of every part of Jesus' model prayer was about "right relationship" to God and our fellow man.  Even our "other centeredness" should be that they all come to the place of intimacy Christ expressed in His life and  in the Lord's Prayer.

You might even be best served to eliminate your pray lists altogether.  If you become deeply intimate with God, you won't need a list.  The Spirit of God will bring every name, every situation, and every specific thing about which He wants you to pray to your mind.  In the most intimate of relationships, His Holy Spirit will actually move your lips and form the words which you would not be able to express yourself.  And GOD WILL BE GLORIFIED and you will be blessed.  When my prayer is uttered from a heart that is as appreciative of Jesus' divinity as much as the thief on the cross beside him, Jesus will respond and quickly and as positively as He did to that thief.