Feng Shui is related to the concepts of yin and yang and Chi. It is meant to maintain good health, wealth, relationships, creativity and more. Feng shui is to create a living and working environment in harmony with nature and the flow of energy, by moving objects to position of elements, color and materials. You can use fountains, mirrors and crystals. Also, Feng means Wind and Shui means Water, So directly translating it, it means Wind-Water.
In Joy luck Club, the idea of Feng Shui can relate to the daughters and mothers. Because of the generations and how that creates a sense of separation, this is an idea of how to try to keep them close. Feng Shui gives off positive energy and creates harmony which could be what the mothers and daughters need to become closer and see the other persons perspective.