Drill-downs are short, relevant videos that are attached to the recipes to provide more information on a particular topic. If you haven't seen them, there are two attached to this recipe:
Palm sugar and
coconut milk/coconut milk products are found in Asian markets and are becoming increasingly popular in the international isle of supermarkets. You can also easily buy these products online. Both are inexpensive and usually cost under $1-2 each (but this depends where you live).
Also depending on where you live, fresh coconuts can also be found in the supermarket from time to time. Hope this helps!