The instructions for your iOS and macOS devices are pretty much the same as those we've listed above. If you have a Mac and you want to search for messages simply open the text app on your computer and use the search bar to type in keywords. Unfortunately, unlike mobile devices, macOS doesn't give us a preview of the message so you'll have to click on each contact until you find the right one. Unless, of course, you know which contact sent you the message you're looking for.