user_turns: <SILENCE> im looking for a cheap restaurant that serves how about vietnamese food vietnamese food <SILENCE> may i have the phone number 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 ? There are restaurants in the cheap price range . What type of food do you want? What kind of food would you like? I'm sorry but there is no restaurant serving moroccan food Could you please repeat that? api_call vietnamese R_location cheap thanh_binh serves vietnamese food in the cheap price range The phone number of thanh_binh is thanh_binh_phone  you are welcome