It's possible to make Postgres do amazing things (e.g. job queue with SKIP LOCKED!) but at what point do you draw the line and use the right tool for the job?
If you wanted to be cheeky you could go ask your CTO if they would foot the bill for someone like 2nd Quadrant to write CJK full-text search into pgsql. ;)
I've done this for some features/issues in random OSS projects and if you feel someone else has the same problem I always feel paying money to have it implemented is well worth it.
We also need stuff like language detection and analysis of mixed language data.
A big advantage of going with a dedicated search tool is that it teaches you what you don't know about search, and it turned out that we knew pretty much nothing.
[1] https://www.elastic.co/blog/implementing-japanese-autocomple...