add func use

Author: marmoure

src/main/xar-resources/data/lucene/lucene.xml

@@ -883,7 +883,7 @@
                 <varlistentry>
                     <term> <code>lowercase-expanded-terms</code> </term>
                     <listitem>
-                        <para>An option used to set whether expanded terms should be lower-cased.
+                        <para>User as An option in <code>ft:query</code> to set whether expanded terms (Analyser input) should be lower-cased,
                         When set to <code>yes</code>, any expanded terms selected by a wildcard, regex, or fuzzy query will be lower-cased.
                         Default value is <code>no</code>.</para>
                     </listitem>