Metadata allows you to find exactly what you want from amongst thousands of images or files. It is time consuming to tag each image, but doing 5 or 10 in your freetime now and then has rewards:
An example: I just typed in "red" in my Gisele folder and got this (edited for size):
Note that "red" will also bring up the word in file names, or partial matches, and that sometimes the "red" is a carpet, necklace or shirt that I tagged in the image.
Honestly, when you get serious about organization, I can't see a better way.