How to narrow a search
Start with the account and one distinctive word. Add dates only if you get too many results. The finder reads the first 20 posts X returns, newest first, or the most popular first if you switch the order. For filters this page does not have, such as minimum likes, language, or posts with video, use the advanced search builder, which runs its search the same way.
Looking for an account's very first post? The first tweet finder is built for that. For a post that was deleted, use the deleted tweet finder. To pull more than 20 results, or to run the same search every day, the guide to searching someone's tweets has a short script.