message: update doc pdf
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  # Nebula Graph
  **Nebula Graph** is the only solution in the world capable of hosting graphs with dozens of billions of vertices (nodes) and trillions of edges, while still only having milliseconds of latency.
  @@ -42,7 +36,7 @@ Apart from [installing from source code](docs/manual-EN/3.build-develop-and-admi
  ## How to Use Nebula Graph
  -See [manual](docs/README.md) or download the [pdf](https://nebula-graph.oss-cn-hangzhou.aliyuncs.com/doc/nebulagraph.pdf).
  +See [manual](docs/README.md) or download the [pdf](https://nebula-graph.oss-cn-hangzhou.aliyuncs.com/doc/manual-en-1204.pdf).
  ## How Can I Contribute
  