This has become a pretty common issue people have with JUCE. I’ve heard that fixing this is one of the big things planned for JUCE 8, which is still a while away.
This thread is a collection of all the times it has been discussed previously, and it also offers a few solutions:
If you draw fonts with AttributedString on macOS or Windows, it should allow font fallback.
If you want a solution that will also work on Linux, and that will also work with default JUCE components without modifications, you might want to check out the solution I propose in my last post here. If you create a font that contains all unicode characters in it, you can reliably draw non-latin text anywhere you want, at the cost of more memory usage and slightly worse startup time.