[DOCS] Corrected track_total_hits def (#62830) (#63180)

Co-authored-by: John Berryman <jnbrymn@github.com>

docs/reference/search/search.asciidoc

@@ -288,8 +288,8 @@ the scores are not used for sorting. Defaults to `false`.
 (Optional, integer or boolean)
 Number of hits matching the query to count accurately. Defaults to `10000`.
 +
-If `true`, the exact number of hits is returned. If `false`, the response does not
-include the total number of hits matching the query.
+If `true`, the exact number of hits is returned at the cost of some performance.
+If `false`, the response does not include the total number of hits matching the query.
 
 `typed_keys`::
 (Optional, boolean) If `true`, aggregation and suggester names are be prefixed