String search in Korean does not work for single characters or partial strings

User on 4071889-zen reported that the search function in Korean does not seem to work correctly in the Android version, if you search for single characters or partial strings it returns no results.

### Expected
That returns results. This works with other devices, in the user case they have tested this as well with the Windows version and works fine.

### Observed
I was able to replicate it.

### Reproduced

- Write 홍길동 anywhere on a note
- Use the search for a single character, or a partial string, for example: 길동
- There are no results.

> simplenote 2.18 (138)
android 10
Model LG V50S and LG V30(V30 android 9)

The issue names no source file or test entry point. Reproduce the Korean search case on Android using a note containing 홍길동, then trace the search path and verify that single-character and partial-string queries return the note without breaking existing searches.

Written by the indexing model from the issue text.