1, "golden grain" usually refers to very rare, precious and high nutritional value grain, such as some ancient varieties or regional grain. This kind of food is rare and hard to find, so the price is high, as expensive as gold.

2. "Gold bars" generally refers to a kind of children's food, which is in the form of gold bars, crisp in taste and sweet in taste. This kind of food is called "gold bars" because it is golden in color and looks like gold.

3. The meaning of the word "golden yellow" is vague, which may refer to some golden yellow articles or substances, but it has no specific meaning. It can be said that the color of an item is "golden yellow", but this statement cannot clearly express the precious or special nature of this item.