The only way I can think of is by applying security access rights to the folders.  I would have an HR group that would have the ability to add, modify, delete, etc... documents in the root folder as well as sub folders.  Then add "everyone" to the root folder with only browse and read access.  At this point the employees will be allowed to see the HR folder but not be able to add or change any of the documents contained in the sub folders.  Now you will need to apply individual security to each of the employee folders where you will uncheck the "inherit rights from parent and include with specified rights", then add the HR group and the individual employee while setting the appropriate rights for the two entries to each folder.  What you should end up with is a folder tree showing all employee folders that will be visible to the HR group, who has the ability to add, change, etc..., and the employee will only see their specific folder, with read only access, containing their documents.