Explanation
Add synonyms to tables and columns: This step applies specifically to Q&A (and not to Power BI reports in general). Users often have a variety of terms they use to refer to the same thing, such as total sales, net sales, total net sales. You can add these synonyms to tables and columns in the Power BI model.
This step can be important. Even with straightforward table and column names, users of Q&A ask questions using the vocabulary that first comes to them. They're not choosing from a predefined list of columns. The more sensible synonyms you add, the better your users' experience is with your report.
Reference:
https://docs.microsoft.com/en-us/power-bi/natural-language/q-and-a-best-practices