diff --git a/docs/en/faq_en.md b/docs/en/faq_en.md
index e006870bfaacef21bbadc6aaade496557c52180f..6f34117fd46ac4db24c4c369e41a3e11ce835a9a 100644
--- a/docs/en/faq_en.md
+++ b/docs/en/faq_en.md
@@ -45,7 +45,15 @@ VALID:
 
 >>
 * Q: What should I do if I want to transform the weights' format from `pdparams` to an earlier version(before Paddle1.7.0), which consists of the scattered files?
-* A: You can use `fluid.load` to load the `pdparams` weights and use `fluid.io.save_vars` to save the weights as scattered files.
+* A: You can use `fluid.load` to load the `pdparams` weights and use `fluid.io.save_vars` to save the weights as scattered files. The demo is as follows. Finally all the scattered files will be saved in the path `path_to_save_var`.
+```
+fluid.load(
+        program=infer_prog, model_path=args.pretrained_model, executor=exe)
+state = fluid.io.load_program_state(args.pretrained_model)
+def exists(var):
+    return var.name in state
+fluid.io.save_vars(exe, "./path_to_save_var", infer_prog, predicate=exists)
+```
 
 
 >>
diff --git a/docs/zh_CN/faq.md b/docs/zh_CN/faq.md
index dd73b674a113c93a444f76134ccaf20cda0e9db8..bd5401475e9be71a91adc3738dd27ff6a42d4191 100644
--- a/docs/zh_CN/faq.md
+++ b/docs/zh_CN/faq.md
@@ -45,7 +45,15 @@ VALID:
 
 >>
 * Q: 如果想将保存的`pdparams`模型参数文件转换为早期版本(Paddle1.7.0之前)的零碎文件(每个文件均为一个单独的模型参数)，该怎么实现呢？
-* A: 可以首先导入`pdparams`模型，之后使用`fluid.io.save_vars`函数将模型保存为零散的碎文件。
+* A: 可以首先导入`pdparams`模型，之后使用`fluid.io.save_vars`函数将模型保存为零散的碎文件。示例代码如下，最终所有零散文件会被保存在`path_to_save_var`目录下。
+```
+fluid.load(
+        program=infer_prog, model_path=args.pretrained_model, executor=exe)
+state = fluid.io.load_program_state(args.pretrained_model)
+def exists(var):
+    return var.name in state
+fluid.io.save_vars(exe, "./path_to_save_var", infer_prog, predicate=exists)
+```
 
 
 >>