Drain tuna and add to a medium bowl. Dice celery and add to tuna along with oil, lemon juice, garlic powder, salt and pepper; mix well.
Slice rolls in half and pull out some of the inside of the roll to make a hole in the center. Add tuna mixture, spinach and kale to the hole and close the roll.
Cut carrots into sticks and cucumber into slices. Serve tuna sandwiches with veggies and oranges.