If you can’t focus your eyes, you have to distinguish between not being able to focus on distant objects and not being able to focus on near objects. If you can’t focus on a distant object, the reason is usually myopia. Myopia causes light from distant objects to be refracted by the refractive system in the eye, and the focus of the image falls in front of the retina, but not on the retina, so it is not clear to see distant objects. In this case, it is necessary to wear myopic lenses to make the focal point shift back to achieve clear vision. If you are unable to focus on near objects, it is usually due to the use of astigmatism medication or presbyopia, and the light emitted from near objects is refracted by the refractive system and falls behind the retina, resulting in unclear vision. In this case, it is necessary to wear glasses in order to make the focal point shift forward on the retina, which can lead to a clear state of seeing near objects.