Cyrillic characters in Browser print are not showing correctly.

When I try to print some cyrillic characters in a label they do not appear correctly. Is there any special thing that I should do to pass the cyrillic characters to the zebra printer through Browser print?

My code:

//setting the priners 
var barcode = "123456789";
var product_name = "Тестов продкт";
var product_price = "2.93 лв."
var zpl = "^XA^CWT,E:ARI000.FNT^CFT,20,20^CI28^BY2,3,57^FT20,170^BCN,,Y,N^FD" + barcode + "^FS^FO20,50^FB370,2^FWn^FH^FD" + product_name + "^FS^FT390,40^FWr^FH^FD" + product_price + "лв^FS^PQ1,0,1,Y^XZ";
var stockReceiptPrinter = null;
var barcodePrinter = null;
$(document).on('ready', function () {  
     BrowserPrint.getLocalDevices(function (result) {       
          result.printer.forEach(function (printer) {            
               if (printer.name === '24a070200057') {                 
                    barcodePrinter = printer;            
               } else if (printer.name === '46j094300866') {                 
                    stockReceiptPrinter = printer;                 
                    stockReceiptPrinter.send(zpl);             
               }        
          });   
     }, function () {});
}); 

I am using BrowserPrint v1.0.4.min.js and zebra-browser-print-setup-1.2.0.3.exe