A erhu fiddle is an item in Evony TKR (The King's Return).
Erhu Fiddle is one of the collection items in the exhibition for the Art Hall. It is one of four parts in the Stringed Instrument Hall. After the set is completed at three stars, you can trade additional Erhu Fiddle fragments for gold.
The description of Erhu Fiddle in Evony TKR says:
Stringed instruments from all over the world. The important exhibits in Stringed Instrument Hall.
Erhu Fiddle is known to potentially be obtainable from opening Artwork Fragment Chest II, Artwork Fragment Chest III, Artwork Fragment Chest IV and Artwork Fragment Chest V. The links for each item are below:
Note: This list may be incomplete.