Update how_to_download_models_en.md

docs/how_to_download_models_en.md

+Model downloads are divided into initial downloads and updates to the model directory. Please refer to the corresponding documentation for instructions on how to proceed.
+
+
+# Initial download of model files
+
 ### 1. Download the Model from Hugging Face
 Use a Python Script to Download Model Files from Hugging Face
 ```bash
@@ -11,3 +16,15 @@ After the Python script finishes executing, it will output the directory where t
 
 Additionally, in `~/magic-pdf.json`, update the model directory path to the absolute path of the `models` directory output by the previous Python script. Otherwise, you will encounter an error indicating that the model cannot be loaded.
 
+
+# How to update models previously downloaded
+
+## 1. Models downloaded via Git LFS
+
+>Due to feedback from some users that downloading model files using git lfs was incomplete or resulted in corrupted model files, this method is no longer recommended.
+
+If you previously downloaded model files via git lfs, you can navigate to the previous download directory and use the `git pull` command to update the model.
+
+## 2. Models downloaded via Hugging Face or Model Scope
+
+If you previously downloaded models via Hugging Face or Model Scope, you can rerun the Python script used for the initial download. This will automatically update the model directory to the latest version.