docs: add more reference links

packages/docs/docs/config/README.md

@@ -208,7 +208,7 @@ Whether to show line numbers to the left of each code blocks.
 - Type: `Function`
 - Default: [source](https://github.com/vuejs/vuepress/tree/master/packages/@vuepress/shared-utils/lib/slugify.js)
 
-Function for transforming header texts into slugs. Changing this affects the ids/links generated for header anchors, table of contents and sidebar links.
+Function for transforming [header](../miscellaneous/glossary.md#headers) texts into slugs. Changing this affects the ids/links generated for header anchors, [table of contents](../guide/markdown.md#table-of-contents) and [sidebar](../theme/default-theme-config.md#sidebar) links.
 
 ### markdown.anchor
 

packages/docs/docs/zh/config/README.md

@@ -202,7 +202,7 @@ VuePress provides a convenient way to add extra styles. you can create an `.vuep
 - Type: `Function`
 - Default: [source](https://github.com/vuejs/vuepress/tree/master/packages/@vuepress/shared-utils/lib/slugify.js)
 
-一个将标题文本转换为 slug 的函数。修改它会影响标题锚点、TOC、以及侧边栏链接生成的 id 和 链接。
+一个将标题文本转换为 slug 的函数。修改它会影响 [标题](../miscellaneous/glossary.md#headers)、[目录](../guide/markdown.md#目录)、以及[侧边栏](../theme/default-theme-config.md#侧边栏)链接的 id 和 链接。
 
 ### markdown.anchor