Using the sales feed to search for bookings is a crucial part of daily operations for all travel companies.
Searching and filtering the Sales feed to see cancelled bookings
Open your sales feed from Bookings > Sales Feed.
Take a look at the search-bar on your sales.
Open the booking status dropdown menu (says Confirmed by default).
Check the Cancelled box and click the search button.
This brings up all your cancelled bookings and when you open the booking itself, you will see more information on the cancellation.