You can make research in your game, which will benefit you with the possibility of upgrades for your coffee shop. All you need to do is to tap on the microscope icon and select one of them to see the details and choose the one it suits you the most at that moment. 

If the button of the research is colored, it means is already available to unlock (if you have enough money for it). but if it's greyed out, it means you need to make one or more actions to unlock it. Tap on the icons below the  "Unlocked by" section and it will take you exactly where you need to take action to continue with the research. 

*Please, take into account that some requirements for some research will be unlocked through Grandpa Bernard's tasks list.