They've uploaded documents to said folder but I can't see them on my end. Any suggestions?
Have you checked the folder on the Dropbox website? If so, and the files are not in the folder, then they haven't been uploaded yet. It could be that they haven't synced from the other person's computer, or they simply haven't added anything to the folder yet. If you can see them in the folder on the website, then they're not syncing down to your computer for some reason.
Once you determine where the issue is (their end uploading or your end downloading), it will be easier to troubleshoot.