[Log Explorer] Adds info about headers and cookies (#24054)

* Adds info about headers and cookies

* Moves section to the end of the page.

* Moves section to log search page

Author: angelampcosta

src/content/docs/log-explorer/log-search.mdx

@@ -55,6 +55,23 @@ FROM access_requests
 WHERE Date >= '2025-02-06' AND Date <= '2025-02-06' AND CreatedAt >= '2025-02-06T12:28:39Z' AND CreatedAt <= '2025-02-06T12:58:39Z'
 ```
 
+### Headers and cookies
+
+To query request headers and cookies, you must first enable logging for these fields using [Custom fields](/logs/logpush/logpush-job/custom-fields/).
+
+The example below shows how to query HTTP requests by date, timestamp, client country, and a custom request header. Be sure to log the specific headers or cookies you plan to query in advance.
+
+```bash
+SELECT clientip, clientrequesthost, clientrequestmethod, edgeendtimestamp, edgestarttimestamp, rayid, clientcountry, requestheaders
+FROM http_requests
+WHERE Date >= '2025-07-17'
+  AND Date <= '2025-07-17'
+  AND edgeendtimestamp >= '2025-07-17T07:54:19Z'
+  AND edgeendtimestamp <= '2025-07-18T07:54:19Z'
+  AND clientcountry = 'us'
+  AND requestheaders."x-test-header" like '%654AM%';
+```
+
 ### Save queries
 
 After selecting all the fields for your query, you can save it by selecting **Save query**. Provide a name and description to help identify it later. To view your saved and recent queries, select **Queries** — they will appear in a side panel where you can insert a new query, or delete any query.