diff --git a/examples/docs/en-US/custom-theme.md b/examples/docs/en-US/custom-theme.md
index 93279e2f0..a5a610295 100644
--- a/examples/docs/en-US/custom-theme.md
+++ b/examples/docs/en-US/custom-theme.md
@@ -51,7 +51,7 @@ Just edit `element-variables.css`, e.g. changing the theme color to red:
 ```
 
 ### Build theme
-After saving the variable file, use `et` to build your theme. You can activate `watch` mode by adding a parameter `-w`:
+After saving the variable file, use `et` to build your theme. You can activate `watch` mode by adding a parameter `-w`. And if you customized the variable file's output, you need to add a parameter `-c` and variable file's name:
 ```shell
 et
 
diff --git a/examples/docs/zh-CN/custom-theme.md b/examples/docs/zh-CN/custom-theme.md
index 1e13a482f..9e1069946 100644
--- a/examples/docs/zh-CN/custom-theme.md
+++ b/examples/docs/zh-CN/custom-theme.md
@@ -51,7 +51,7 @@ et -i [可以自定义变量文件]
 ```
 
 ### 编译主题
-保存文件后，到命令行里执行 `et` 编译主题，如果你想启用 `watch` 模式，实时编译主题，增加 `-w` 参数。
+保存文件后，到命令行里执行 `et` 编译主题，如果你想启用 `watch` 模式，实时编译主题，增加 `-w` 参数；如果你在初始化时指定了自定义变量文件，则需要增加 `-c` 参数，并带上你的变量文件名
 ```shell
 et