Perhaps you should try some spelling variations:
about titles » about tithes, about tables, about ties
ebook title » book title, book titles
nijhoff op » nijhoff _, nijhoff j
op title » sop title, shop title, job title
title 1 » title _, title a
title 2 » title _, title a

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 about titles 2006 ) OR ((( nijhoff op title 1 ) OR ( nijhoff ebook title 2 )))).
• Adding a wildcard symbol may retrieve word variants: (( nijhoff about titles 2006 ) or ((( nijhoff op title 1 ) or ( nijhoff ebook title 2 ))))*.