In this example, we will exclude some 'text' property of nt:unstructured node from indexind. And, therefore, node will not be found by the content of this property, even if it accepts all constraints.
First of all, add rules to indexing-configuration.xml:
<index-rule nodeType="nt:unstructured" condition="@rule='nsiTrue'">
<!-- default value for nodeScopeIndex is true -->
<property>text</property>
</index-rule>
<index-rule nodeType="nt:unstructured" condition="@rule='nsiFalse'">
<!-- do not include text in node scope index -->
<property nodeScopeIndex="false">text</property>
</index-rule>