The warmth of something is the heat that it has or produces.
She went further into the room, drawn by the warmth of the fire.
她被火的温暖吸引着,走进了房间。
The warmth of something such as a garment or blanket is the protection that it gives you against the cold.
The blanket will provide additional warmth and comfort in bed.
毯子能让你睡觉时感觉更温暖更舒适。