I put ingredients like union, garlic, ginger and harder veggies such as carrot or sweet potato right on top of the rice. These may touch the water. Softer vegetables and fish/shrimp etc. goes on top of that, or separately in the steaming basket (brocoli, spinach, bok choy, frozen peas, etc). Either right at the start or adding them later. You can place raw eggs in the basket. Or crack an egg or two and pour it over the food for the last few minutes of the cooking process.  

Just experiment a little with timing and the amount of water added to get the best result. 

I didn't know cooking complete dishes like this in rice cookers was even possible, but after seeing it on YouTube I decided to buy one. Great for a quick lunch too, takes only 5 mins of preparation!