Perhaps you should try some spelling variations:
mechanical efficiency » technical efficiency
international theatre » international treaties, international trade, international test
international centre » international context, international case, international capital
mechanical science » clinical science, mechanical stretch, mechanical impedance
lectures » lecture

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: (((( international centre for mechanical science, courses AND lectures ) OR ( international centre for mechanical efficiency, courses AND lectures ))) OR ( international theatre for mechanism science, courses AND lectures )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( international centre for mechanical science, courses and lectures ) OR ( international centre for mechanical efficiency, courses and lectures ))) or ( international theatre for mechanism science, courses and lectures ))".
• Adding a wildcard symbol may retrieve word variants: (((( international centre for mechanical science, courses and lectures ) OR ( international centre for mechanical efficiency, courses and lectures ))) or ( international theatre for mechanism science, courses and lectures ))*.