Facebook keeps record of everything and everyone you search on Facebook just like Google. It keeps track of your every search activity and save it as history. That is why when you type on Search Bar, it immediately shows the result you have previously searched.You can also see what you have searched and what you have done in the activity log.
You can see the search history by default in Goggle’s privacy option. No person can breach this privacy until or unless your phone gets hacked. Only through hacking or in case of lost device where Facebook is active, all your Intel regarding search and other data can be checked or mishandled.
In order to remove the search data, first go to Search Bar on Facebook. As you click on it, it will give the search data. There will be edit option on the right of search. Click edit option, you will get search history page. From there delete all searches from the search history at once or delete a particular search by clicking the box near it and choosing delete.
You can now easily secure your FB info by following these steps.