@trinhminhhieu Hello again! I have seen and dry run your code, but the issue is not your coding, I guess your pipeline in config.yml as you are developing the vi (Vietnamese bot), so you need to decide the pipeline first; I am sharing some link for your reference how you can customise the pipeline, I hope this will help you. Even, I can understand the pressure about your project and university for the same.
Reference Paper (check page 4): https://www.researchgate.net/publication/348390901_Enhancing_Rasa_NLU_model_for_Vietnamese_chatbot
Reference Vietnamese Community: Rasa Community in Vietnam
Reference Github (Its 2 year old- just for idea don’t try to run): https://github.com/heraclex12/vietnamese-chat-with-rasa
I’m really sorry, I tried my level best to help you!
Urgent Note: I can be totally wrong in this too, If any other person seeing this post please try suggest the solution for the same.
Currently the bot is working as you can see in below post, I am not expert in pipeline on any other language except English 