Unable to search network drives with OS X - short answer
This is here not as a question but rather to summarize some point on a very long thread >> https://discussions.apple.com/thread/3194502
If you are facing the issue in this title
Keep these in mind.
1 - Make sure indexing is 'on' for the SMB volume: sudo mdutil -i on (path-to-smb-volume).
2 - Since the index is stored locally on the client's local volume, the server MUST remount with exactly the same name each time or it can't pair up the server with the local index.This applies to any of the protocols that work with Mac; SMB, FTP, AFP etc. In other words, if the server name changes or if it is a localdrive whose name has changed since the last succeful spotlight index, a subsequent index won't pair up therefore you won't find things, this is expected so try to avoid changing the name of the drives or SMB server to prevent indexes from pairing up.
Hope this helps you avoid a long read on that thread above.
iMac, OS X Mountain Lion, iMac early 2012, 3.4Ghz i7 32GB RAM