2010 s18d 130k km need help!

[JIAN2000]

Hello, everyone!
I bought a 2010 s18d a month ago and now drive 130,000 km.Everything was ok before, but two weeks ago, I encountered blue and white smoke coming from the engine compartment during driving. When I opened the engine cover, I found that the smoke came from the position of the turbine and catalytic converter, but the smoke did not appear every time I drove. Who knows why?Is it still possible to drive at high speed?I plan to go to Croatia next week. It is estimated to drive 2000 kilometers. Is there any problem?
Thank you for your attention!