This is a Google search operator. Used alone, it limits results to files hosted on Google Drive. When combined with a name (“kristopher rodas imaginaria”), it implies the searcher believes there is a publicly accessible Drive folder — possibly sharing art, PDFs, or game builds.
You can find official copies of the book and its sequels through the following platforms: imaginaria kristopher rodas site drive.google.com
The term “Imaginaria” commonly refers to: This is a Google search operator