The Vietnamese word "béo mắt" literally means "to fatten the eyes," and it is often used in the context of sleeping well or sleeping to one's heart's content. When someone uses this phrase, they are expressing the idea of having a good, restful sleep that leaves them feeling refreshed and satisfied.
While "béo mắt" primarily refers to sleep, it can also imply indulging in rest and relaxation, especially after a period of stress or hard work. You might use it metaphorically to refer to taking a break or enjoying leisure time.