Using the AEM query builder, will search a content which is available in specified directory only. This query will not search the content in sub directories, or not even child of the child directories.
Open AEM Query Builder Debugger: http://localhost:4502/libs/cq/search/content/querydebug.html. Add the following options to perform the search.
--> path=? // On which path this query will perform the search operation.
--> path.flat=true // will look the content only in the specified directory.
--> fulltext=? //name or keyword which you are searching.