Many Asian people learn cooking from their families, but in these cultures, the learning style may be very different from what you expect.
If we went into the kitchen and asked our parents: “how many teaspoons of sugar do you add into that dish, and how hot do you make the pan?” we may not get the answer we want. Sometimes they will answer “I am not very sure. It depends. You should just pay attention, instead of asking”, or even “You ask too many question, stay out of the kitchen and stop bothering me!”
In my family's kitchen, when our parents were making soup, stir-fried dishes, and so on, they would add salt, soy sauce, sugar, pepper, then taste a little with a spoon, then add a little more of this or that. That was often how they measured the ingredients, so they really couldn't say what was the 'correct' amount.