Here's a tweak you can use to further refine your Google image searches; you can add a URL parameter to the search results to specify the color of images returned. From my limited testing, the use if the URL parameter does a better job of returning specific image colors than by just adding the color to the search terms.

To add the URL parameter, perform your image search in Google. When you get the results, go up to the address bar and add the following to the end of the URL in there:

&imgcolor=YOUR_COLOR

where you replace YOUR_COLOR with the color of images you want. I don't know the full set of colors that Google is allowing. But all of the basic colors (red, blue, yellow, orange, white, black, green, yellow) seem to work. So as an example, if you want to update your search to shown on white results, you'd add this to the URL in the address bar:

&imgcolor=white