Perhaps you should try some spelling variations:
lessons three » lessons taken
papers titles » paper titles, paper title, paper titled
papers tiles » papers times, papers time, papers rules
lesson three » session three
iot world » lost world, art world

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: 2008 ((iot world) OR (post world)) ((papers titles) OR (papers tiles)) ((lesson three) OR (lessons three)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "2008 ((iot world) or (post world)) ((papers titles) OR (papers tiles)) ((lesson three) or (lessons three))".
• Adding a wildcard symbol may retrieve word variants: 2008 ((iot world) or (post world)) ((papers titles) OR (papers tiles)) ((lesson three) or (lessons three))*.