@joseph I did the same thing with Google, but it often had results that were licensed. In fact, Google says right on the search result that you are responsible for the use.
There are so many good sources for free pictures, most of the time it isn't worth messing around. We don't need another "Crying Michael Jordan
"Crying Michael Jordan"? I am not familiar with that story. can you please explain?
I am providing two links. If you have any experience in legal documents, go straight to the second one. If that is a new subject, then read them in order.
In this case, where we all stand to receive financial benefit for the use of the image, it opens the possibility. Not probable, but possible.
Here is a link to a media article on it:
http://business.financialpost.com/legal-post/how-using-a-viral-meme-of-michael-jordan-crying-could-land-you-in-a-messy-lawsuit
And another from a legal perspective:
https://heitnerlegal.com/2016/02/25/is-there-a-cause-of-action-surrounding-crying-michael-jordan/
A social post is not commercial use, unless your post is just one image that you use repeatedly. There were no lawsuits for memes unless they were used as a commercial product or advertising.
I think that pretty much describes social media.
This is a good overview of what is at stake:
http://www.aaronkellylaw.com/sue-over-a-meme/
I think it is difficult, and most people are not at risk, but there still exists a risk. Defamation, publicizing private data/info, false light, invasion of privacy, copyright infringement and unauthorized us of property are all named in that link.
Like I said, the risk may be small, but always "think before you meme".