Perhaps you should try some spelling variations:
"notes dissertations" » "two dissertations", "three dissertations", "brief dissertations"
"some dissertations" » "five dissertations", "six dissertations", "proper dissertations"
"four dissertations" » "_ dissertations", "two dissertations"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("some dissertations") OR ("four dissertations"))) OR ("notes dissertations")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"some dissertations\") OR (\"four dissertations\"))) or (\"notes dissertations\"))".
• Removing quotes may allow a broader search: (((( some dissertations ) OR ( four dissertations ))) or ( notes dissertations )).
• Adding a wildcard symbol may retrieve word variants: (((("some dissertations") OR ("four dissertations"))) or ("notes dissertations"))*.