Google New TIp - Do Not Include The Word!!

In recent days I have come across several search results where Google is showing the

Tip: These results do not include the word "WORD".

at the end of the results. Its also showing an option via which you can see the results which contain that specific results.

Question is..
Why Google is neglecting some specific word in a phrase?

Its not that the word doesn't appear cause Google is showing an option to see the results with the word included.

Here is an example(click to enlarge)

Google Calculator Error...!!!

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Here is the url: Google error url

Here is the Query: 399,999,999,999,999 - 399,999,999,999,998

Relevancy, Google, Adwords !

So while researching for one of the client site, I come across with this MOST RELEVANT ADWORDS AD By Google. Take a look at that and rethink about Google insisting on Relevancy, relevancy, relevancy....


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