Spark 2.8.3 error font unicode vietnamese

I have ubuntu 18.04 LTS when i installed spark 2.8.3 failed font unicode vietnamese .
Ex:
I type : “cần”
Result: Screenshot%20from%202018-11-08%2013-57-52
P/s: I had Microsoft’s TrueType Core font in ubuntu 18.04 LTS

I think same happens with Chinese on Linux. And this is some general problem with fonts in Spark. Unfortunately, Spark doesn’t have active developers to fix that. https://issues.igniterealtime.org/browse/SPARK-1639