DOCSP-16097 Clarifying Intro (#174)

* reworded intro

Author: kyuan-mongodb

source/usage-examples/find.txt

@@ -4,13 +4,15 @@ Find Multiple Documents
 
 .. default-domain:: mongodb
 
-You can query for multiple documents in a collection with
-``collection.find()``. The ``find()`` method uses a query document that you
-provide to match the subset of the documents in the collection that match the
-query. If you don't provide a query document (or if you provide an empty
-document), MongoDB returns all documents in the collection. For more
-information on querying MongoDB, see our
-:doc:`documentation on query documents </fundamentals/crud/query-document>`.
+You can query for multiple documents in a collection with the
+``collection.find()`` method. The ``find()`` method uses a query
+document to determine what to include in the result set. A query
+document can contain query operators. Query operators are keywords that
+begin with a ``$`` that let you specify complex query behavior. If you
+don't provide a query document or if you provide an empty document,
+MongoDB returns all documents in the collection. For more information on
+how to use query documents and query operators, see our :doc:`guide on query documents
+</fundamentals/crud/query-document>`. 
 
 You can also define additional query options such as
 :doc:`sort </fundamentals/crud/read-operations/sort>`

source/usage-examples/findOne.txt

@@ -14,12 +14,13 @@ Find a Document
 
 You can query for a single document in a collection with the
 ``collection.findOne()`` method. The ``findOne()`` method uses a query
-document that you provide to match only the subset of the documents in the
-collection that match the query. If you don't provide a query document or if
-you provide an empty document, MongoDB matches all documents in the
-collection. The ``findOne()`` operation only returns the first matched
-document. For more information on querying MongoDB, see our
-:doc:`documentation on query documents </fundamentals/crud/query-document>`.
+document to determine what to include in the result set. A query
+document can contain query operators. Query operators are keywords that
+begin with a ``$`` that let you specify complex query behavior. If you
+don't provide a query document or if you provide an empty document,
+MongoDB returns the first matched document. For more information on how
+use query documents and query operators, see our :doc:`guide on query documents
+</fundamentals/crud/query-document>`. 
 
 You can also define additional query options such as
 :doc:`sort </fundamentals/crud/read-operations/sort>`