The restaurant is trying to attract more customers, and the new menu is an important 'piece of the puzzle'. [=an important part of what is being done]
Ecologists no longer view different species as independent, but instead see them as pieces of the same 'jigsaw puzzle'.
His strange behavior is a 'puzzle' to his friends. [=his friends don't understand the reason for his strange behavior]
(..) The program took just people every six months. There were three blank lines after "high school" to list more education. Try and sleep. It's late. It's a puzzle measuring just inches by inches on each side... ...made up of multiple colors that you twist and turn... ...and try to get (..)2006 The Pursuit of Happyness