Can I buy a return ticket from Yiwu to Changsha in Wenzhou?

Yes, tickets for the nationwide network are available at the ticket offices of major stations in all provinces, only 5 yuan handling fee is added. However, in recent days, hard seat and hard sleeper tickets are not easy to buy, because it is time for the annual welcoming soldiers to send veterans, and many trains have been cancelled. I suggest you leave in a few days. However, the EMU has no influence.