I am also asking this question on the Google Product Forums.

Basically, the Google Drive folder is synced onto my data partition. Files are present on my HDD, the whole folder is indexed, but nothing inside it comes up in my Windows search results.

I have tried rebuilding the index from scratch, unindexing and re-indexing the Drive folder, and making sure it has full permissions as per this link:

Windows 7 Index Search does not work in Google Drive folder - Super User

Also, "Allow files in this folder to have contents indexed" option is on.

I had this problem in Windows 8.1 as well, but I forgot how I fixed it.

Any ideas?