The option to search in Lifesum using your voice is available in all areas of the app where you can enter text. The feature is accessible in most supported languages and can be accessed from the built in keyboard on your Android device. The option is marked with the icon of a microphone.

 

Depending on the phone model you can either use the standard keyboard, in the case of some phone models who do not support all languages you need to switch the keyboard and use the Google option instead.

 

Please find more information here: https://support.google.com/gboard/answer/2781851