Where have you seen rule-based text classification being applied?

I wrote a rule-based text classification app specialized in my language (Vietnamese) and would like to know where else this app is useful. For example if you input the prompt (which is use a bunch of keywords), e.g. `fish 50k`, then it will automatically label/classify the prompt like this:
- Object: fish
- Type of Object: food
- Place of transaction: market
- Type of place of transaction: offline
- Consumer: myself
- Type of consumer: myself
- Price: 50000 …

app classification example fish keywords language languagetechnology prompt text text classification the prompt will