# Page Not Found

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## Suggested Pages

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- [Class 10: Giới thiệu WebSocket](https://docs.quangkhoi1228.com/lap-trinh-nestjs/class-10-gioi-thieu-websocket.md)
- [NestJS module](https://docs.quangkhoi1228.com/nestjs/nestjs-module.md)
- [Class 15: Project 6: Hoàn thiện project](https://docs.quangkhoi1228.com/lap-trinh-reactjs/class-15-project-6-hoan-thien-project.md)
- [Class 12: Project 5: Hoàn thiện form data](https://docs.quangkhoi1228.com/lap-trinh-reactjs/class-12-project-5-hoan-thien-form-data.md)
- [Class 07: Authentication – JWT](https://docs.quangkhoi1228.com/lap-trinh-nestjs/class-07-authentication-jwt.md)

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### Option 1 — Ask a question (recommended)

Perform an HTTP GET request on the documentation index with the `ask` parameter:

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```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

### Option 2 — Browse the documentation index

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Use this to discover valid page paths or navigate the documentation structure.

### Option 3 — Retrieve the full documentation corpus

Full export: https://docs.quangkhoi1228.com/llms-full.txt

Use this to access all content at once and perform your own parsing or retrieval. It will be more expensive.

## Tips for requesting documentation

Prefer `.md` URLs for structured content, append `.md` to URLs (e.g., `/lap-trinh-nestjs/class-10-gioi-thieu-websocket.md`).

You may also use `Accept: text/markdown` header for content negotiation.