Jackrabbit Text search in Arabic PDF File

I am able to perform text search for arabic text file successfully using the following code in Jackrabbit. But for an Arabic PDF file, the same search is not working. If I give some of the non-arabic text inside the fle, its giving me the correct result, but if I give an araic word i开发者_StackOverflownside the file, its not giving me any result.

Query query = queryManager.createQuery("select * from [nt:resource] AS resource where contains(resource.*, '%القط%')", Query.JCR_SQL2);

 QueryResult result = query.execute();
 RowIterator ri = result.getRows();

     while (ri.hasNext()) {      
     Row row = ri.nextRow(); 
     System.out.println("Row: " + row.toString()); 
 }

Thanks

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Possibly PDFBox could not parse the file. In this case, there should be a warning in the log file.