Perhaps you should try some spelling variations:
"nijhoff book title 21" » "nijhoff boston title 21", "nijhoff op title 21", "nijhoff book titles 21", "nijhoff ebook title 21", "nijhoff book table 21", "nijhoff book title 1", "nijhoff book title 2", "nijhoff book title _"
"nijhoff _ title 26" » "nijhoff _ title 2", "nijhoff _ title 25", "nijhoff _ title _"

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: (("nijhoff _ title 26") OR ("nijhoff book title 21")).
• Removing quotes may allow a broader search: (( nijhoff _ title 26 ) or ( nijhoff book title 21 )).
• Adding a wildcard symbol may retrieve word variants: (("nijhoff _ title 26") or ("nijhoff book title 21"))*.