docs: add a link from Search to Queryables

docs/notebooks/api_user_guide/4_search.ipynb

@@ -96,7 +96,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "The three search methods introduced below accept pretty much the same parameters, which are described further down the page."
+    "The three search methods introduced below accept pretty much the same parameters, which are described further down the page. Note that if you wish to know which parameters are available to use in a search, you may the [queryables API](./5_queryables.ipynb)."
    ]
   },
   {