Google's AI has been trying to better connect and understand meaning of words instead of doing basic text matching. In the old days you could rank simply by keyword stuffing. Google now wants to see related words and concepts in your content.
Do a search for "tax accountant in (insert your own town here)" and pay attention to the words Google is bolding in the SERPs. They are bolding "tax" and "accountant". They are also bolding close matches like "accountants" and "accounting" which isn't new at all. If you look even closer you will see Google is also bolding the personal names of tax accountants. Google AI has figured out that "John Smith" is a tax accountant for your local town.
So when you are creating content to rank in Google, make sure you respect Google's AI. Feed the AI natural content that is ripe with keywords and context. Avoid non-descriptive terms and pronouns. Favor more specific identifiers and terms. Treat the names of business owners as a brand name and naturally embed it in content. This type of content is often what your users want anyway.
If you still can't figure out what keywords are relevant for your industry run a quick TFIDF test. Don't blindly follow the results but use these results to brainstorm ways to improve the value of your content.