How to analysis the result of django debug toolsbar?

From the debug result ,i can see my website Browser timing is really long. Basically i create 13000 item for the blog table. Seems like it takes not a long time to do sql query.
The debug result

My questions is how can i Identify bottlenecks from debug result. Why it loads so slowly ,takes near 20s .How can i reduce the domContentLoadedEvent and domloading Time.
Thanks.

---