(DOCSP-6956) Adding section on number of source docs returned from pipeline (after revert) (#257)

* (DOCSP-6956) Adding section on number of source docs returned from pipeline

* Formatting for review

* Changes based on feedback

Author: zach-carr

source/images/charts/source-document-count.png

@@ -27,8 +27,8 @@ View Source Documents
 ---------------------
 
 Once you have selected a :doc:`data source <data-sources>` for your
-chart, you can view 20 sample documents from that data source by
-clicking the :guilabel:`View Source Documents` from the
+chart, you can view up to 20 sample documents from that data source by
+clicking :guilabel:`View Source Documents` from the
 :icon-fa5:`ellipsis-h` menu.
 
 .. note::
@@ -51,6 +51,14 @@ data source that considers:
 
 - Filters applied in the :ref:`Filter Tab <filter-tab>`
 
+The :guilabel:`Source Documents` modal displays the number of documents
+from your data source that match your query conditions, although only
+20 of the documents are viewable as samples.
+
+.. figure:: /images/charts/source-document-count.png
+   :figwidth: 80%
+   :alt: The View Source Documents modal displays the document count just above the document samples.
+
 .. _view-aggregation-pipeline:
 
 View Aggregation Pipeline
@@ -81,7 +89,7 @@ Get Chart Data
 --------------
 
 After you have configured a valid chart, you can view and export the
-underlying data as a table. To view the chart data, click the 
+underlying data as a table. To view the chart data, click 
 :guilabel:`Get Chart Data` from the :icon-fa5:`ellipsis-h` menu. Each
 row in the table represents a data point.