Rabbits love variety but they also have basic feed requirements, your bunny will, when purchased from a breeder come with a small bag of food that it is use to & that you can mix in with your own to assist with the transition into your life.
I purchase several ingredients from the produce store and make up my own mix. This is based on chaff, grain mix, pellets and additives which contain pro-biotics and vitamins/minerals suitable for rabbit & cavy basic dietry needs. Grasses,hays,fruit and vegetables are also required to keep them happy and healthy.
Remember cavies (guinea pigs) cannot produce vitamin C and therefore require fruits/vegetables DAILY to overcome this.
Oaten and/or Meadow hays are normally readily available from your produce store and some pet stores and should be a part of the daily diet or at the very least 3 times a week when varied with fresh fruits and vegetables. Hay's should be a lovely lush colour, never feed yellow or grey coloured hays.
The Kizma gang love all of the following and all has been or is grown for them: Cauliflower (leaves & vege),broccolli (leaves & vege),beans,Asian vegetables, corn cobs, strawberries, chard (spinach), capsicum, kiwi fruit, apple (no seeds), celery, cucumber, endive to name but a few things of an exhaustive list.
Remember to WASH all fruit & vegetables well.
If in doubt of any plant please do an online check (check out my links page) or ring a breeder for advice. Your best port of call for ANY bunny or cavy question is a breeder (well several, as opinions vary) rather than pet shops.