is there any bullet train from shenzhen to Yiyang, Hunan. Depart schedule. thanks

There is no direct bullet train between the two places.
It is suggested to take G-trains to from SZ North Railway Station to reach Changsha Railway Station. Then you can take a taxi from the railway station to reach local West Bus Station where you can find the direct buses to reach Yiyang directly.
The train schedule from SZ to Changsha, you can search on https://www.travelchinaguide.com/china-trains/.

I afraid not,the only train leaving from SZ to YY is k9076 ,depart at SZ east station at 19:43 and the jurney will take you 11 hours.

thanks Lo n Simon. any idea how can i reach the railway station from Hong Kong airport or Baoan airport. thanks again