When Facebook announced Graph Search, they emphasized that they designed it with privacy in mind and yet made two different statements. First, M. Zuckerberg said that it’ll give access only to « things that people have shared with you »   while T. Stocky said that «[you] can only search for what [you] can already see on Facebook».
I define the « content I share with you» as the content you can see on my timeline which is in fact a subset of the content you could see about me on Facebook. But Facebook has a different definition and considers « content shared » as everything about me that is visible, even if it normally requires a considerable effort to find it.

Finding pictures with Graph Search

Facebook made it clear that hiding photos on your timeline is no longer enough to prevent people from seeing them. With graph search, it’s now very simple to find all the photos of someone that are visible to you.
For instance, if one of your friends is tagged on pictures that he decided to remove from its timeline, these “hidden” photos will appear in graph search if you have access to them.
It was already possible to find « hidden » pictures a friend was tagged on but it required a considerable amount of time and effort: you had to go through the list of all his friends and check their pictures in case your friend might appear on some of them. Unless you were really creepy, your friends were safe to assume that most of their « hidden » pictures would not be viewed by you. That’s no longer the case and to control who can see your “hidden” pictures you’ll have to delete tags or ask your friends to limit the pictures visibility .

Removing tag is not the solution

Tags is not only a feature used to annotate content, it’s also used to know when someone comments a picture you appear on.  If you delete the tag, you lose the possibility to quickly know how people react to a photo. Not removing a tag is different than sharing a picture. Assuming that people want to share every picture they’re tagged on is wrong, especially when they’re a « share » button that allows them to do precisely that.
Unlike posts on your timeline, tags don’t have to be reviewed before they appear in Graph Search. To control photos of you that will appear in graph search, you have to frequently visit Facebook and remove unwanted tags. You have no option to proactively control your image on Facebook other than relying on your friends to not tag you without your consent.

The case of friends list

Strangely Facebook did not adopt the same definition of “sharing” with the “Friends list”. Assuming we’re friends; if you’ve decided to hide your friend list from your timeline, I can try to recompose it by visiting each of your friend’s timeline and check that you appear as a mutual friend. It would require knowing some of your friends first, but that’s fairly easy if they posted something on your timeline. By iterating this process, I could retrieve a subset of your friends. Like photos you are tagged on, this subset is presumably shared by you but won’t appear if I search for the list of your friends.