You can search the Library's catalog to find full length monographs on an author (or a particular work) as well as essays and chapters appearing in books.
When searching library catalogs, add the keywords 'criticism and interpretation' to the author's name and you'll surface works of criticism that cover several of the author's texts:
Césaire, Aimé -- Criticism and interpretation
Huxley, Aldous, 1894-1963 -- Criticism and interpretation
Atwood, Margaret, 1939 -- Criticism and interpretation
In the case of someone as famous as Shakespeare, the catalog's subject headings can get specific to the level of individual works and particular aspects of individual works.
Shakespeare, William, 1564-1616. Tempest
Shakespeare, William, 1564-1616 -- Stage history
When you find the perfect book on your topic, use the Library catalog's subject headings to find more books like the one you've got.
For the sake of example let's say I'm interested in how Shakespeare deals with nature and the natural world in his plays. I've found a promising book 'Shakespeare and ecology'.
When I click on the book's title, I get a detailed record of the book which includes the table of contents and assigned subject headings that will help me locate more books.
Shakespeare, William 1564-1616 -- Knowledge -- Natural history looks very promising. So I click on that heading and find this list of books.
These look perfect for my purposes. By clicking on the title of any of these books, I can review the tables of contents and see if there are chapters of interest.