Ask a question, then stop talking. The next thing they say is usually the true one.

Silence after a question does work that more words cannot. Most people fill a pause with the thing they were holding back, because quiet feels like a problem they are supposed to solve. Jump in with a follow-up or your own guess and you hand them an easier answer to give.

Try it once this week with someone you genuinely want to understand. Ask, then count slowly to five in your head and let the gap sit there. The first answer tends to be the polite one, and whatever arrives after it is usually closer to true.