Ramen, Health Drink, Rubber Ball and Helmet are the items you want to look for. You can find them in the restaurant, cafe, or the shop. Make sure to use the toys a handfull of times and keep checking in your scale meter that you have the intelligence icon that you want. I have noticed that it will change if I feed certain food items or play games etc, and then once done I quickly go find the toy and play with it to get back to the one I wanted it to be.