Like humans, dogs also have basic food needs. They should be getting enough protein, along with carbs, iron and such.
I've had dogs since I was a little kid. So did my mum since she was little. And I'm proud to say that we've NEVER given them dog food (which is obviously artificially made), and all of them lived their lives healthily.
What we feed our dogs is homemade flat bread, which we eat daily too, with extra of bones and meat. You can find leftovers of meat easily from a butcher's shop which are pretty cheap. If your dogs have never eaten raw meat, boil it, but not so much that the juices run out.
If you're thinking of being creative, you can mince/shred the meat, add veggies like cabbage, broccoli etc, and make patties of the mixture. You can also add plain rice, but it has to be freshly boiled, as old rice can cause severe food poisoning in them.
Keep one thing in mind, don't give them extra food. Just twice a day. Provide them with plentiful of water, and occasional milk if you can afford it. Avoid anything with acid (like grapes and lemon), sugar and alcohol.
You can get a list of the food items here.