In order for the test to be performed correctly, allow the following distance between subject and screen:
Clover left eye with your left hand, ensure to avoid applying pressure to the eyelid. Read the letters on the screen beginning at the top. Once completed, repeat with the right eye.
If you were able to read as easily with both the left and right eye, chances are you have a strong central visual acuity. If you are unable to read all the lines, you definitely have vision problems. A comprehensive exam, performed by an optometrist is required.