Note: it's might be easiest to search using the name of the particular object or the name of the observer. If a query box is empty then it will not be constrained in the database search.
Uncheck the Bell and Crimea boxes so that it only looks for RCT data (that makes the search a little quicker if nothing else).
Once you have set up your search parameters, click "Execute Search" or to start again press "Restore to defaults".