High-lighting is not default feature so we must set it in jcr-config.xml, also excerpt provider must be defined:

<query-handler class="org.exoplatform.services.jcr.impl.core.query.lucene.SearchIndex">

   <properties>

      ...

      <property name="support-highlighting" value="true" />

      <property name="excerptprovider-class" value="org.exoplatform.services.jcr.impl.core.query.lucene.WeightedHTMLExcerpt"/>

      ...

   <properties>

</query-handler>

Also, remember that we can make indexing rules, as in the example below:

Let's write rule for all nodes with primary node type 'nt:unstructed' where property 'rule' equal to "excerpt" string. For those nodes, we will exclude property "title" from high-lighting and set "text" property as highlightable. Indexing-configuration.xml must containt the next rule:

<index-rule nodeType="nt:unstructured" condition="@rule='excerpt'">

   <property useInExcerpt="false">title</property>

   <property>text</property>

</index-rule>