minor #8484 Update finder.rst (flip111, javiereguiluz)

This PR was merged into the 2.7 branch.

Discussion
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Update finder.rst

symfony/symfony#8871 (comment)

Commits
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cc8853e Minor reword
69ecceb Update finder.rst

Author: xabbuh

components/finder.rst

@@ -55,6 +55,13 @@ the Finder instance.
     :phpfunction:`iterator_to_array` method, or get the number of items with
     :phpfunction:`iterator_count`.
 
+.. tip::
+
+    The ``Finder`` object doesn't reset its internal state automatically, which
+    means that results are always added to the previous ones. Instantiate a new
+    object or call :phpfunction:`create` on the existing object to reset the
+    previous state.
+
 .. caution::
 
     When searching through multiple locations passed to the