So you've got an adult dog with behavior problems. The dog's behavior or your behavior?
The reason I am asking is: Our dog's present behavior is a reflection of the behavior of its Pack members. That's primarily the dog owner (you and me) and often family members (spouse, children, cat or other dog). Sure, the dog's upbringing and earlier treatment plays a significant role, yet to change the dog's present behavior we must change our own behavior. This is the only way we can lessen the impact that the dog's upbringing and earlier treatment has on the dog's present behavior. This is even true for a traumatized dog, whether traumatized from a shelter experience or from a prior owner.
We cannot change our dog's heredity and upbringing anyway. We cannot undo missed socialization. We cannot undo a trauma. But what we can do is: We can change our own behavior in a way that changes our dog's behavior the way we desire! Thus that we no longer see it as a behavior problem.
Most dog owners seem to address this by becoming stricter in their Obedience Training, because they think that's all that can be done. After months (or years) of trying to change the adult dog's behavior this way, they get frustrated, or they give up, or they even abandon the dog.
They should have known better from the start though: We cannot introduce or broaden or strengthen Obedience Training for an adult dog and hope that the dog will be responsive to that. The adult dog won't. Like you, the adult human being, won't be responsive if your partner or children tried to get you "more obedient". Same with dogs, adult is adult.
Instead, the real solution is to focus on Behavior Training and Dog Socialization.
PLEASE NOTE: Posting a fragment of your overall dog problem in the comments below is not going to help. Provide complete details if you really seek the right solution. Of course we have a page for that as well: Dog Problem Consultation.