Android - Scroll to a particular date in Whatsapp

You can also do the following without using an extra app specialized on searching through WhatsApp.

Go to options (the "..." symbol) -> "more" -> "send chat per email". This way you can export a txt file including date, time and message content and send it per e-mail. This file can be imported to excel or smth and filtered using normal functions of the program you import it to.