I strongly believe that whatever is destined for you will reach you automatically.. this might exclude the necessity to pray for achieving what you want.. I therefore believe that you dont need to specially mention it to God what you want..he knows it anyways.. Greed, for few specific things, sometimes forces me to force God in my prayers to fulfil my worldly desires.. but then I stop and this second thought strikes my mind that what if I deserve more than what I beg for in front of God.. greed again!