My wife has been breastfeeding our baby boy since birth. And milk demand has naturally increased over time as baby grows. How can she increase her milk supply or should we go for a mixture of milk powder feeding and breast milk feeding? Any advice or recommendation?

breast milk is better for baby. eat more food which is good for boosting supply and of coz need to drink at least 3L of water(soup/Milo/juices) if she DL then shouldn't have problem unless not enough wet diapers.. if she pump, she need to pump 2-3 hourly and cannot skip motn pump too.