Problem with "content access" (module) and permission "View own unpublished content"
I've just found some interesting information about my problem. Maybe it will help someone else.

In fact, it's seems impossible to resolve this problem in a proper way. 

There is a very good article about that: Access Control module prevents View of user's own unpublished content, and an issue on drupal.org

If we want to see our own unpublished content in workbench, we have to go in view and make:


Go to query settings
and check Disable SQL rewriting option


It's not very good solution like he said but we can't do anything else for now.