here to save the day.
All you have to do is enable the feature under the Tools menu or press Ctrl+Alt+R, and you will be treated to a nifty little sidebar that sits to the right of your document and lets you perform a quick Google search. In addition to a regular search, you can search specifically for quotes or images. You can then easily insert the quote into your document, and the autorship information will be automatically attached.
As it stands now, this is already a handy tool that lets us do something we often need to do without the extra step of switching windows. But this tool will become indispensable when Google rolls out Semantic Search. Right now, it's easy to find a nice picture or a good quote for your document without leaving the page. But when you're searching for specific information, you still have to click on a search result and open it in a new tab. With Semantic Search, Google will be able to spit out all the facts you need directly within Docs. So when you're typing up that astronomy paper, you don't need to switch tabs every five minutes just to find the distance to the Sun, the circumference of the Earth, or the year Galileo discovered the moons of Jupiter.
The feature is rolling out over the next few days. You can check to see if you've got it at drive.google.com.