Those are good sources of Vitamin E, Arachyd. Wheat germ (2 teaspoons daily per rabbit) or wheat germ oil (5-6 drops) can also be used.
Vitamin A is found in dark leafy greens such as dandelion, parsley, carrot tops etc. You can google for other sources.
These things are only going to help if the problem lies with a deficiency of these nutrients. There could be other causes of failed breedings. But certainly adding these supplements, in normal amounts, will do the rabbits no harm. I remember one person on HT who was expeiencing similar problems. (Silosounds, if you want to look up his posts). There was a dramatic improvement when he added fresh sprouts (grains sunflowers and so forth) to his rabbits' diet. Even I was amazed!