This can occur due to weakening of accomodation power of your eyes.You can get your eyes checked by opthalmologist for further clearing your doubt.Uptil then you can put cineraria eye drops 2 drops twice in day in both of your eyes .It will help you out to improve your accomodation and also helps preventing cataract
for a longer time.
You Also have to concentrate on your eye hygiene ,means wash with cold
water atleast 5-6 times in day.cleam them properly.Wear glasses when you go out or during driving
hope this helps,