http://www.highernature.co.uk/ShowProductFamily.aspx?ProductFamilyID=300Higher Nature almost Human, Superdog Ultimate Nutrition, developed with Nick Thompson BAHVS etc.
If your dog eats very little you may be better off providing him with a nutritionally denser food so it will have the necessary nutrition. EG Orijen which is grain free and very little is required.
Also with a dog that is picky, feeding TINY meals more often can help. So spread the meals out as far as you can, which is possible using Orijen for example.
Twice a day feeding is average for a pup of this age. How much less than the recommended intakes (as on the packet) is the dog ACTUALLY having or is your view based on your personal opinion of what it SHOULD be eating?
Remember all dogs have differing appetites and needs...............
Is your dog skinny, lethargic etc?