Dogs have fewer tast busters as compared to humans. The taste is not as important a motivational factor for dogs as smell. The Ceralac you offer to your dog has fresh aroma which attracts your dog's nose while Drools which is full of preservatives has a standard chicken smell which dogs tend to get used to after first and second intake. So, unless your dog is starving, he won't even smell dry commercial food, no matter whether you feed Drools, Royal Canine, or Taste of Wild.
Considering the fact that your dog is just 45 days, I won't suggest you switching to home-cooked meal. You can continue feeding Ceralac. Apart from that, you can try this trick: Boil water till it steams up giving vapours and sprinkle it on the kibbles. You may also sprinkle a pinch of chicken soup powder into the boiling water and then add into the kibbles.
Could you also try to feed a better brand then Drools. Drools and Pedigree are high in animal byproduct. The best food right now in the market is Eukanuba. After 3 months, you can switch to home-cooked fresh meal which your dog will certainly love!!!!