image manager view thumbnails

when adding or changing an image in a product, category or other area the image manager does not show the image thumbnails so you have to know the name of the image ahead instead of being able to pick an image by sight.
How can I change this and is this how it is supposed to be set?

More info needed.
What OpenCart version?
What browser are you using?
Where exactly are you seeing the issue? "Walk" us through the steps you are doing.