Update search term (#5923)

docs/core_docs/docs/concepts.mdx

@@ -104,11 +104,11 @@ and is an integral part of LangServe.
 As your chains get more and more complex, it becomes increasingly important to understand what exactly is happening at every step.
 With LCEL, **all** steps are automatically logged to [LangSmith](https://docs.smith.langchain.com) for maximum observability and debuggability.
 
-### Interface
+### Runnable interface {#interface}
 
-<span data-heading-keywords="invoke"></span>
+<span data-heading-keywords="invoke,runnable"></span>
 
-To make it as easy as possible to create custom chains, we've implemented a ["Runnable"](https://v02.api.js.langchain.com/classes/langchain_core_runnables.Runnable.html) protocol.
+To make it as easy as possible to create custom chains, we've implemented a ["Runnable"](https://api.js.langchain.com/classes/langchain_core_runnables.Runnable.html) protocol.
 Many LangChain components implement the `Runnable` protocol, including chat models, LLMs, output parsers, retrievers, prompt templates, and more. There are also several useful primitives for working with runnables, which you can read about below.
 
 This is a standard interface, which makes it easy to define custom chains as well as invoke them in a standard way.