Select question in ortho view

hello there, I am beginner in Blender, before learning blender I used MAYA to make animation. In the beginning more & more operating problem let me frustrated.

How can I select all overlap vertex in ortho view ?Like picture,it is a cube in top ortho. I want to select all vertex in one side.But try more time,only can select one vertex. Did I miss something?

Disable ‘Limit Selection to Visible’

or go into wireframe view

Thanks! get it! I need to see the basics tutorial more times.

Thanks for your answer!