The advanced search syntax can be used to search for electronic documents that have been associated with an electronic file with a particular file name extension. The syntax for this type of search is shown below.
The term Ext specifies the file name extension that an electronic file must have before the associated electronic document can be considered a valid search result.
The first sample search will find all electronic documents that have been associated with Word documents. The second sample search will find all electronic documents that have been associated with web pages.
{LF:Ext="doc"}
{LF:Ext="htm"} | {LF:Ext="html"}