  In this study, we build a chatbot system in a closed domain with the RASA
framework, using several models such as SVM for classifying intents, CRF for
extracting entities and LSTM for predicting action. To improve responses from
the bot, the kNN algorithm is used to transform false entities extracted into
true entities. The knowledge domain of our chatbot is about the College of
Information and Communication Technology of Can Tho University, Vietnam. We
manually construct a chatbot corpus with 19 intents, 441 sentence patterns of
intents, 253 entities and 133 stories. Experiment results show that the bot
responds well to relevant questions.
