The Vietnamese word "nghẽo" primarily refers to something that is small, weak, or lacking strength. It can be used to describe a person who is feeble or has limited physical ability. In the context of your example, "nghẽo" is used to emphasize how something, like a jade (which is usually strong in its symbolic representation), seems incapable of performing a difficult task, such as pulling a heavy cart.
In more advanced conversations, "nghẽo" can be used metaphorically to describe situations or ideas that are weak or lacking in substance. For example, you might say, "Lập luận của bạn nghẽo quá, không thuyết phục được ai cả," meaning "Your argument is too weak; it cannot convince anyone."
While "nghẽo" primarily describes weakness, in some contexts, it can also point to inadequacy in skills or abilities, indicating that someone is not up to a certain standard.