Since Google Drive does not offer a broader search for 'owner contains @alumni.brown.edu', this tool should help. It's a Google Sheet with a custom Google Apps Script that iterates through files in your Drive.

To use this on your account, follow these steps:

1. Access the file: https://docs.google.com/spreadsheets/d/13cYMmvvQy6qt_EMinxTemohuM7G5Ef4Hmz3S65nPRr0/edit
2. Make a copy. Go to File > Make a copy. 
   1. You will be prompted about this and there will be a notice about an attached script. Click Make a copy.
3. Once you've opened the file, you should see Custom Scripts at the top. This may not be immediate and you can try refreshing the doc until it appears.
4. Click on Custom Scripts and click on Find Alumni Files.
5. You will receive an authorization request. Click OK.
6. A new window will open. Select your Brown email address from the list.
7. Scroll down and click on Allow.
8. Once this is done, the script is authorized on your account. Click on Custom Scripts > Find Alumni Files again to start the script.
9. Follow the prompts and wait for the script to finish.
   1. You will be prompted how many files to iterate through in your account. The larger the number, the longer it will take for the script to run.

The authorization prompt should only appear the first time you run this. Afterward, you can run it at will. Just note that the script is set to clear the existing sheet before proceeding.