It looks like Google is testing a related searches box directly in the mobile version of Google Image search. I personally tried multiple ways to replicate this feature, but I am not yet seeing it. Some are - and when you scroll through images in Google Image search on your mobile phone, Google may show you a box that lets you expand your query with "related searches."
Here are screen shots from @RobinRozhon and @javigarcia on Twitter:
This related searches feature is something Google has been testing both on mobile, desktop, web search, image search and other verticals of search for years.
I do not know if this one will roll out or not, although some believe it is rolling out now.