James 4:3 And even when you do ask, you don’t get it because your whole motive is wrong - you want only what will give you pleasure. - N.L.T.
It is imperative that you pray in the will of God, otherwise you could be asking for things that could be harmful. You may also be coveting something that is not His will. Picture in your mind that a ship is entering a harbor late at night.
On the shore are four green lights that the ship must line up with. If the pilot steers his ship in a straight line toward the four lights he will not hit the rocks. You have four things that you can look at to determine the will of God which are: 1. The Word of God. 2. The guidance of the Holy Spirit. 3. Circumstances. 4. Timing.
Before you pray for something, it is better to ask the Lord what His will is for that item. Sometimes He doesn’t want your plan, because He has a far better one for you.