I believe there are two reasons why God has a hard time searching our heart:
1. Availability meaning, we do not give him time and we are too busy for him, in other words we are saying that he is not a priority in our life.
2. We limit his access in our life. We give him certain areas of our lives but others are off limits. You can have this God but you can’t have this addiction, you can have this Jesus but not this idol and ultimately, we pick and choose what God can have and it begins to block him out of areas of our life.