Better search plugins

docs/.vuepress/config.js

@@ -169,6 +169,8 @@ module.exports = {
     plugins: [
         '@vuepress/plugin-back-to-top',
         'vuepress-plugin-smooth-scroll',
+	'vuepress-plugin-fulltext-search',
+	['flexsearch'],
         ['vuepress-plugin-medium-zoom',
             {
                 selector: "img",