I am having the same issue. Usually the the file highlights in yellow and the most relavant tot he search goes to the top and the other non relevant files dont show up at all. This is how it worked...

All I did was change the size by manually adding the MinThumbSizePx entry into the registry.
Open up regedit and navigate to:...

Check out Classic Shell. Classic Shell - Start menu and other Windows enhancements
It is a replacment start menu that I like better than the default and it has an option to change the color and...

Yes I did it works flawlessly.

This worked for me. Simple regedit entry