How to highlight Partial Urdu Characters

How to highlight Partial Urdu Characters

i write a code that search for a sub string and highlight it with html markup <b><b/> 

  1.  if(originalString.contains(searchString)){
     searchString=originalString.replaceAll(ctxt, "<b>"+searchString+"</b>");
     out.println(searchString);
     }


it works well with English, but if i use URDU (similar to Arabic) it break



there red one shows the break and green show how it should be.

can jquery is able to solve it? Any suggestion or help would be greatly appreciated.