Just to walk you through my process, I started with the A-Z Databases libguide, which can be accessed from the library homepage through the Search Databases link in the Get Started section. I then selected the Literature tab.
I had luck in a few databases. I searched the title of the poem in quotes, like this: "The doubt of future foes".
First I tried ProQuest Research Library: Literature & Language. I searched the title, and checked the Full Text box under the search bar, then ran the search. When you access the articles, you'll see your search terms highlighted, so it's easy to pick out the sections that discuss the poem.
I also tried Literary Sources and ran the same search. The limiters on the left have several options to narrow the results. I chose Literary Criticism under Content Type. There are several promising articles. Again, the title is highlighted, so you can find discussion of the poem easily.
EBSCO eBooks had a few results. Using the same search, I then clicked on the Subject Heading on the left (then the blue Show More link under the short list of subjects) to expand all the topics. I checked off all that mentioned literary criticism for appropriate time frames, countries, monarchs, etc. When you click on the titles, the bottom of the detailed record page shows the pages that mention your search phrase. You can click those to go straight to that page. There is also a "Search within this book" option on the top left.
Finally, we have a couple of print books that discuss your poem and are worth checking out. They are Elizabeth I and her age : authoritative texts, commentary and criticism and Elizabeth I : the voice of a monarch . Just click on the title link to access the record and see the call number and availability. I used a subject search, su:Elizabeth I, Queen of England, 1533 1603 Literary art . You can copy and paste into the search bar.
FYI, our book (print and eBook) catalog is called WorldCat (linked below) and is also accessible on the homepage. It's the default option, All Books in the Library, in the drop-down menu in the Go Straight to the Good Stuff section. Just hit the Go button.
Bring your COM ID to check the books out. You will have to log in with your last name and 7 digit COM ID to access the other databases (not WorldCat) off campus.
I'm also including a link to our Working with Literature libguide. The tabs on the top have helpful resources for writing about literature. The last tab links to How to libguides for all of the databases listed above. They include search tips, how to get your citations, etc.