Try hugging the hedge line, Use the noise of the river streams road ect to your atvantage, Use the wind also to your atvantage, Pick rabbits that sitting or the ones thats out the furthest,
Try lamping a few sheep feilds with pig netting on slows the rabbits down abit and helps the dog, Rock the lamp on the rabbit to help the dog,
And most importantly get out there and learn from your mistakes fellah, Get out as much as you can