How can I find a specific topic on facebook private messages?

[nixies]

Other than scrolling up, which takes forever to do especially when the topic you're looking for took place a long time ago, is there any way I can search for it using a search engine or something? Before facebook change their messages layout they have a search engine on the upper right corner of the page where you can just search for a specific word or sentence and when you click enter it will show the results of the messages that you or the person you have been messaging that contains that word or sentence.

[Terence]

There is a search option in new layout also. it is just above the persons list you have chatted