code: public String postProcessing(String text){
  		
  		String [] lines = text.split("\n");
  		String ret = "";
  
  		for (String line : lines){
  			String [] words = line.split("[ \t]");			
  			String templine = "";
  			
  			for (String currentWord : words ){
  				//break word into syllable and check if one of it is not valid vi syllable
  				String [] syllables = currentWord.split("_");			
  				boolean isContainNotValidSyll = false;
  				
  				for (String syllable : syllables){			
  					VnSyllParser parser = new VnSyllParser(syllable.toLowerCase());
  					
  					if (!parser.isValidVnSyllable()){
  						isContainNotValidSyll = true;
  						break;
  					}
  				}
  				
  				if (isContainNotValidSyll){
  					String temp = "";
  					
  					for (String syll : syllables){
  						temp += syll + " ";
  					}
  					
  					templine += temp.trim() + " ";
  				}
  				else templine += currentWord + " ";
  			}
  			
  			ret += templine.trim() + "\n";
  		}		
  		
  		return ret.trim();		
  	}
docs: Do post processing for word segmentation: break not valid vietnamese words into single syllables.
  
  @param text the text
  @return the string