When you search HoyaSearch use a combination of keywords like Silk Road History Sources
Examples of primary source books:
Sounds of the Silk Road: Musical Instruments of Asia by Use the following keywords to find a primary source in the catalog or in a database:
Source (s)
Document(s)
Narrative(s) - Memoir
Art(work)
Correspondence - Letters
Speech(es)
Try a combination of keywords in the Subject field to focus your search. Examples:
An Armchair Traveller's History of the Silk Road by 
Art, Religion, and Politics in Medieval China by 
Civilizations of the Silk Road by 
Spatial Dunhuang by 
Journeys on the Silk Road by 
