This documentary was banned from Czech tv and is not listed on IMDB.
Available here too.
if it disappears from Youtube, again.
Another related video is listed on IMDB, The Battle of Kosovo:
On June 28th 1389 at Kosovo Polje, the army of Serbian emperor Lazar made a stand against the advancing Ottoman forces of Sultan Murat, resulting in a great battle which would later inspire Serbian folk tales and poems about courage, sacrifice, betrayal and tragedy. The movie was made for the 600th anniversary of the event.
Also see this previous post: The Kosovo Tragedy – where are the churches?