When i close my eyes and squeeze them, then when i open them again, i get clear vision. why is this?

Possible dry eyes: The most common reason why people can have vision that blurs in and out is dry eye. While the eye is open, the tears evaporate, drying out the cornea surface and blurring the vision. Squeezing the eyes closeed causes a slight tearing response which lubricates the cornea, smoothing its surface and improving the vision. An easier way to achieve this is to use artificial tears 3-4 times per day.

Your eyes are dry : It is very common to have fluctuations in vision if your tear film is unstable which is the case in people with "dry eye". If your eyes are irritated, and tend to cycle between irritation, tearing and blurry vision, this is a good sign you have dry eye as a diagnosis. When you close your eyes, it is likely that you are rewetting the cornea and temporarily alleviating the problem.