With the today’s update, you may specify how to sort the results for Twitter and Google Plus. Below the each query input field, there is a “Result ordering” dropdown. For Twitter, there are “recent”, “popular” and “mixed” options:
For Google Plus, “recent” and “best” options are available.
Switching between one result type to another may affect the list of items you’ll get. What type to use depends on your own preferences and a query term.