how to list all paper titles of all categories

There are 2 submenus under menu “news”, one is “company news”, another is “industry news”.
There are also 2 subcategories under category “cat-news”, one is “cat-company news”, another is “cat-industry news”.
There are many papers in “cat-company news”, and many papers in “cat-industry news”.
I want to list all paper titles in the 2 subcategories when I click “news”. But now, when I click “news”, it just shows the list of 2 subcategories, it does not show the paper title’s list of the 2 categories.
How can I do that?
Thank you for your answer.

The first question is - what type of content you use ? Defualt Joomla! articles or K2 items ? Did you check the view settings in menu item configuration ? (list child categories, amount of articles etc ?)