Perhaps you should try some spelling variations:
"nijhoff book title 20" » "nijhoff boston title 20", "nijhoff op title 20", "nijhoff book table 20", "nijhoff work title 20", "nijhoff book time 20", "nijhoff book title 2", "nijhoff book title 10", "nijhoff book title 21"
"nijhoff book titles 26" » "nijhoff boston titles 26", "nijhoff op titles 26", "nijhoff book entitled 26", "nijhoff book intitled 26", "nijhoff book tables 26", "nijhoff work titles 26", "nijhoff book times 26", "nijhoff book titles 2.9", "nijhoff book titles _", "nijhoff book titles 1"
"nijhoff ebook title 20" » "nijhoff ebook table 20", "nijhoff ework title 20", "nijhoff ebook time 20", "nijhoff ebook title 2", "nijhoff ebook title 10", "nijhoff ebook title 21"

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 ebook title 20") OR ("nijhoff book title 20"))) OR ("nijhoff book titles 26"))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"nijhoff ebook title 20\") OR (\"nijhoff book title 20\"))) or (\"nijhoff book titles 26\"))*".
• Removing quotes may allow a broader search: (((( nijhoff ebook title 20 ) OR ( nijhoff book title 20 ))) or ( nijhoff book titles 26 ))*.