Currently I need the database to using programming language to custom search my interests.

Something like, no option to choose language to filter the search result, or do if conditional to manga release years to filter search result.

We do not currently have a method to download the database directly.

You can filter by type and year in the API which should be sufficient for your specific need.

For example: I want years 2020 2021 2022 2023 2024 contained in search result, and I want any result of series has Chinese name but do not check has Chinese translation or not, then I want that series description do contains a word or string.

To check this series do has Chinese name or not, I need to use regex expression to make sure name has any Chinese characters.

I didnt see there is clear documentation about search API.