Praying over the Word...has the effect of shaping our minds and hearts, so that we desire what the Word encourages us to desire, and not just what we desire by nature. That is why the prayers of Bible-saturated people sound so differently. Most people, before their prayers are soaked in Scripture, simply bring their natural desires to God, In other words, they pray the way an unbeliever would pray who is convinced that God might give him what he wants: health, a better job, safe journeys, a prosperous portfolio, successful children, plenty of food, a happy marriage, a car that works, a comfortable retirement, etc. None of these is evil. They're just natural. You don't have to be born again to want any of these. Desiring them - even from God - is no evidence of saving faith. So if these are all you pray for, there is a deep problem. Your desires have not yet been changed to put the glory of Christ at the center.
John Piper