Articles about immigration to America from England.
To get scholarly sources your best bet is to use Databases by Subject and go to the History & Genealogy page. This page has all the best databases to use for history.
Once there, you can search for articles. When you do search, you'll have to come up with more specific terms than you have in your question. In other words you really need to have some idea of why they emigrated before you search and use those key word in your search.
I am assuming you are wanting scholarly sources on why the English emigrated to the colonies in the 17th century. If you do not have a general idea of reasons, you can get an overview from Britannica. Here is a link to the 1450-1763 tab in the United States History LibGuide. There are direct links to key factors for this in the Get an Overview from Britannica box. In fact, the name of the links are terms you could probably use in a search, but you should really take a look at the content on Britannica to have a a better idea of the reasons.
Once you've done that, go back to the History & Genealogy page in Databases by Subject and search EBSCO Academic Search Complete with your new search terms. You may need to do separate searches on several of the reasons to get enough articles. Or you could just focus on one, depending on your assignment. You can limit to Academic Journals under Source Types, or limit to Scholarly (Peer Reviewed) Journals under Refine your results.