update readme

Author: gspgsp

README.md

@@ -4,7 +4,7 @@
 
 This plugin provides full-text search functionality for **VuePress v2**. It is designed to address the search needs of VuePress sites, offering a fast and efficient way to search through the content of your site. The plugin automatically generates a search index from your site's pages and provides a simple way for users to search through the content.
 
-This plugin is built to work with the latest version of VuePress, but also maintains backward compatibility for VuePress versions up to **v2.0.0-beta.43**. It ensures smooth transitions for users upgrading their VuePress projects.
+This plugin is built to work with the latest version of VuePress.
 
 ##### Features
 
@@ -13,11 +13,31 @@ This plugin is built to work with the latest version of VuePress, but also maint
 - **HMR Support**: Includes Hot Module Replacement (HMR) code to allow live updates of the search index during development.
 - **Search Index Generation**: A script that generates the search index by extracting relevant data from your site's pages.
 
-##### Installation
+##### Installation & use
 
 To install the plugin, follow these steps:
 
 1. **Install the plugin** via npm:
 
    ```bash
    npm install vuepress-serach-plugin --save
+
+2. ***usage** in config.js
+    ```
+    import fullTextSearchPlugin from "vuepress-serach-plugin";
+    
+    export default defineUserConfig({
+        plugins: [
+                fullTextSearchPlugin({
+                    locales: {
+                        '/': {
+                            placeholder: 'Search',
+                        },
+                        '/zh/': {
+                            placeholder: '搜索',
+                        },
+                    },
+                })
+            ],
+    )}
+    ```