Q&A
Q&A (question and answer) is a very flexible way to let your visitors get insights they want typing queries in natural language.
Ask a question using natural language in Power BI
Very good examples of possible queries for end users of reports : https://powerbi.microsoft.com/fr-fr/blog/qna-december-2018-update/
Q&A tips : https://docs.microsoft.com/en-us/power-bi/consumer/end-user-q-and-a-tips
Radacad : http://radacad.com/power-bi-q-how-to-ask-questions