Why can't I find elements on a pop-up window using selenium webdriver for python after successfully switching windows in firefox?

I cannot find any elements in a new window, even after applying a long wait

Using a firefox browser, I am able to use selenium to click on a link that opens a new window.Then I switch to the new window after looking up the window handle.

winHandles = browser.window_handles
NewWindow = browser.window_handles[1]
browser.switch_to_window(NewWindow)

I know that I am switched to the correct window because I am able to maximize the new window that popped up when I clicked on the link.

browser.maximize_window()

What could be going wrong that is preventing me from being able to find elements and how can I fix it?