user_turns: <SILENCE> restaurant unusal vietnamese vietnamese food <SILENCE> phone number phone number thank you thank you good bye
system_turns: Hello , welcome to the Cambridge restaurant system . You can ask for restaurants by area , price range or food type . How may I help you ? What kind of food would you like? I'm sorry but there is no restaurant serving unusual food Could you please repeat that? api_call vietnamese R_location R_price thanh_binh is a nice place in the west of town serving tasty vietnamese food Can I help you with anything else? The phone number of thanh_binh is thanh_binh_phone Can I help you with anything else?  you are welcome