Rhomboids are a weak link for many lifters. Target them like this. Use a close grip attachment and pull down to the sternum. Flare the elbows out at a 90-degree angle.
Heavy bent-over dumbbell or barbell rows are still best for building an impressive back, but the rhomboid pulldown is a great finishing exercise for adding more volume without taxing you as much as the bigger movements.
Use a V-bar or close grip attachment and pull down to your sternum while flaring your elbows out at a 90-degree angle. Keep your trunk stable to prevent excessive rocking.
There are 3 ways to simulate growth: Inflict structural damage, increase neural activation, or prevent blood and oxygen from entering the muscle during a set. Few exercises do all three, but the constant tension alternate curl does.