Rascals are always sociable, and the chief sign that a man has any nobility in his character is the little pleasure he takes in others company. Arthur Schopenhauer

Google dorks for searching Google Drive.

Spreadsheets: inurl:/spreadsheets/d/ "<KEYWORD>"

Documents: inurl:/document/d/ "<KEYWORD>"

Files: inurl:/file/d/ "<KEYWORD>"

Folders: inurl:/drive/folders/ "<KEYWORD>"

Obviously, replace <KEYWORD> with the search term.

For example, typing inurl:/spreadsheets/d/ "passwords" into the Google Search textfield will redirect you to this search page, with all kinds of goodies.