How To Look Up Image On Google. Tap back up & sync. Make sure back up & sync is turned on.

Here's one workaround if you're searching an image you found online (instead of a picture you took yourself): Make sure you back up your photos and videos to the right google account. Once you click on the camera icon, a menu will open up allowing you to either paste the url of the image, or upload a picture from your computer that you wish to search.