Here are some great resources to help you build a more complex chatbot:

• chatbotslife.com/dialogflow-restaurant-bot-tutorial-1-45ce1d3c0ab5.
• tutorials.botsfloor.com/building-your-own-chatbot-using-dialogflow-1b6ca92b3d3f.
• marutitech.com/build-a-chatbot-using-dialogflow/.