Since the tool is focused on tracking real-time data, it starts monitoring your queries from the moment you've created them. That means that from the moment you created a query, you can be sure that the tool will catch your mentions precisely.
Mediatoolkit can fetch older data, but no longer than three previous months. That applies if you are a new client or a Mediatoolkit user for less than three months.
If you go to Set date range on the right side of the tool and set it to the last three months, you might be able to get some of the mentions if they were previously collected in our database.