> Google: undefined is not a function -> 800.000.000 results
You didn't put quotation marks around the second, and the first has no spaces, so this is not a fair comparison. "undefined is not a function" with the quotation marks has 449,000 results.
I don't doubt that there are many results for "undefined is not a function", but I feel quite confident saying there aren't anywhere near 449,000. If you ask google for just 111 of them, you'll get "In order to show you the most relevant results, we have omitted some entries very similar to the 110 already displayed."
> Google: undefined is not a function -> 800.000.000 results
You didn't put quotation marks around the second, and the first has no spaces, so this is not a fair comparison. "undefined is not a function" with the quotation marks has 449,000 results.