https://www.christianbook.com/when-god-answers-prayer/bob-russell/9781451676235/pd/676235
Some people are "prayer plodders": They pray not because prayer comes easy but because they believe in its power. Others are "prayer professionals": they are gifted in the practice of prayer; prayer seems to flow authentically and effectively from their hearts. Whether you are a plodder or a professional, you can be a prayer warrior-one whose prayers are powerful and effectual -- even efficient.
The simple message of this book is that prayer works. Even if prayer doesn't always come easily or your prayers aren't always answered as you'd hoped, you will come away from this book convinced that God rewards genuine prayer. Open the pages of this book and see for yourself what happens when God answers prayer!