Some files not being synced

Hello - some of my attached documents are not being synced. I have checked that the "Synchronize attached files" is checked "For my entire library". The files are on my desktop but not appearing in the online library, and also not appearing on my synced laptop. I noticed that two missing ones are two word files, but the laptop document directory has 2,379 files in it, and the desktop 2,405 so there are others; it's not clear if this is a one-way failure or if some of the laptop docs are not on the desktop. Thanks Martin