You can take train to travle around most of chinese cities.
ChengDu to ChangZhou has three trains available:
1. K292/K289 16:40 leave from ChengDu, 02:57 arrive in ChangZhou (Price, regular seat: 242RMB, regular sleeper: 438RMB, soft sleeper: 671RMB)
2. K284/K281 17:46 leave from ChengDu, 06:49 arrive in ChangZhou (Price, regular seat: 266RMB, regular sleeper: 480RMB, soft sleeper: 738RMB)
3. K698/K695 19:42 leave from ChengDu, 04:47 arrive in ChangZhou (Price, regular seat: 242RMB, regular sleeper: 438RMB, soft sleeper: 671RMB)

there is not direct train from ChengDu to CangZhou, you have to transfer from Xi'an.
You can take any of those train from ChengDu to Xi'an
T8 11:40 leave from ChengDu and 00:24 arrive in Xi'an
K880 12:25 leave and 05:33 arrive
K166 13:15 leave and 05:16 arive
K870 14:50 leave and 09:03 arrive
K292/K289 16:40 leave and 09:38 arive
K386/K387 18:24 leave and 09:47 arrive
k698/K695 19:42 leave and 11:07 arrive

then take this train from Xi'an to CangZhou
K214 14:03 leave from Xi'an and 06:40 arrive in CangZhou

thanks Mr. Hariss for your reply.