After more than 15 years covering everything Apple, it’s with a heavy heart we announce that we will no longer be publishing new content on iMore and the iMore forums will be closing as of November 1st, 2024.
If you refer to Facebook Messenger, what "recent searches" do you mean? Do you mean people in your thread menu? If so, long press down on a person, then push up. You should see the option to delete conversation. If not, register in and provide more info.