Yes, it sometimes happens that the eyes of a person have different eyesight. There are several reasons for this phenomenon. First of all, you may usually lie on bed on one of your side when you are reading a book or watching TV. This kind of habit will make your eyes see objects in different distance. As time goes by, the crystalline lense of your eyes will get use to different distances, thus making your eyes have different visions. Besides, if the posture when you are writing is wrong or abnormal, for example, writing with head inclined, will also lead to different eye sight of your eyes. In total, you should pay attention to your habits of using eyes in case the condition gets worse. Eat more foods rich in vitamin E which is good for your eyes. Do some eye exercises regularly and allow your eyes to have adequate rest. If necessary, use some eye drops. The most importantly, do not lie on bed when you are reading or watching TV, and sit upright when you are writing.