Use Double Quotes Around Words that are Part of a Phrase

     example:  "great barrier reef"

     Specify Words that Must Appear in the Results
     Attach a + in front words that must appear in result documents.

     example: sting +police

     Specify Words that Should Not Appear in the Results
     Attach a - in front of words that must not appear in result documents.

     example: python -monty

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