Buttons going below screen in landscape mode

I am learning iphone app development and I am using swift. I took the lynda tutorial and I have created a very basic UI which is View Controller > View . In the View I added a segmented control, two buttons(horizontal, facing each other), three labels, one textarea and two other buttons(horizontal, facing each other).

So I have these UI components arranged vertically and I used 'Reset to suggested constraints' and made all the buttons equal width and equal height and everything is fine in potrait mode but as soon as I go to landscape mode the last two buttons disappear, if I add a constraint from bottom edges the whole UI gets messed up i.e. only one label and part of an upper button appears.

What should I do to make all the UI components visible both in potrait and landscape mode?