If Google actually did that sort of thing, their very first product would be an improved anti-paranoia medication.
Go ahead and get in line.
Do you know about Google’s secret hiring process?
If your search terms have been relating to a position google is looking to hire, Google offers you a hiring challenge right there! Yes, a possible job at Google based on your search terms right away.
Here’s an example below:
Now to answer your question: Theoretically, yes google can steal your idea. Practically, I don’t think Google would ever do that.
You remember google’s tagline?
‘Don’t be evil’