Facebook is currently in the process of rolling out a new feature to the site. When looking at your activity, you’ll see what you searched on the website. It also contains the date and time – so if someone goes onto your Facebook, hopefully they don’t look at who you stalk. As said by Facebook:
In addition to your other activity, you’ll be able to see the searches you’re making on Facebook. Just as you can choose to delete any of your posts, you can use the same inline control on Activity Log to remove any of your searches at any time. It’s important to remember that no one else can see your Activity Log, including your search activity.
Good thing it’s private and nobody else can see it!