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image searching has been explained here several times and using several ways in recent months.Google Reverse Image Search (GRIS)YandexTineyeAre just a few of the services you should be using together. Try searching the threads and reading what's already been clearly written.
Out of those 3, Yandex finds more fake photos than the other 2.Don't forget the other trick some people are using on AW now. i.e. reversing the image to fool searches. Easiest way to check is if using a PC is to save the image, then right click on it and chose edit photo. You then have the ability to flip it around again and then do your photo checking.
A site imgops (External Link/Members Only) allows one to call upon various tools to explore images - including calling upon reverse image searchers from google, yandex and tineye. It's really only for convenience as you only have to drag or upload an image once rather than load it into each engine separately.
Yandex fails where others succeed so you should not be using only one service.