Hi, kindly advise the best train solution to travel from ningbo to zhengzhou, on any day?

Well, there are direct trains to Zhengzhou. They depart at 09:36 and 14:11 from the main railway station, and the trip takes about 17-20 hours.

To save time, you can take a bullet train to Nanjing South (2.5 to 4 hours) from the main railway station. Then, take a bullet train to Zhengzhou (5 hours). :)