Why Do I See Moving Black Or Brown Dots And Cloudy Lines In My Left Eye, Especially Against Light Backgrounds?

I am in UAE, in my left eye vision eye can see a black/brown dot. Before it was one and now there is two dots and some little cloudy lines connecting the dots and surroundings. It is more visible when i am looking into any white wall or some light colors? When I tried to look on that spot it keeps moving but if concentrated to look straight point then i can see that dots in a same position