Changing the file view in Windows Explorer to Thumbnail results in the text file name being hidden although the image thumbnail is visible. This is actually a toggle, so that when viewing file thumbnails you can control whether or not you want the text filename below the image thumbnail.
In the 'Choose Details' window of the folder the 'Name' option is selected (it's not even possible to deselect it). Hold down the shift key when switching to thumbnail view to hide the file names. Do it again to bring them back.
Another way to enable or disable filename visibility in the thumbnail icon view is to open the folder while holding down the shift key. Hold down the Shift Key, Right-click while keeping the Shift key depressed, Choose Open while still keeping the Shift key depressed.