Superstition

Superstition is a strange word for me which I had never heard it before. After my Philippine teacher (I think you mean "Filipino") in italki explained it with several samples, I began to know ("know" sounds strange here.  I'd use "to see", "to understand") it's a quite an interesting topic to discuss.
Everybody must know (more natural: "must have heard") many stories or tales about superstitions from his parents or other elders when he was a child. Some of them I think there have no any truth or logic in their background to back them up. I clearly remember that my grandfather warned me against opening an umbrella in a room: otherwise I will would never grow taller in the future. I tired it and nothing happened, of course. Some other superstitions may have some truth in them. For example, a person, even an emperor, was not suggested supposed to sleep in a big bedroom in ancient times. Otherwise, he or her she would lose vigour and easy to fall ill easily. I think the true reason is that the big room cannot easyily be to be keep kept warm at night. If anybody got a cold, it will would have been a serious disease at that time.