How to change an image description

To change an image description, you must change the text next to the image and the image's alt and title attribute values. Then you'll have to wait a bit for the robot to recognize the changes and re-index them. After it's been re-indexed, the image is displayed in response to other queries.

Note. Yandex finds images that best match the user's query. However, image captions aren't the only ranking factor, so the words from the query may be missing from the pages that contain the images.