Perhaps you should try some spelling variations:
international congress » international conference
international centre » international theatre, international context, international capital
mechanical sciences » mechanical science, technical sciences, chemical sciences
international case » international capital, international context
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) OR (international case))) OR (international congress)) for mechanical sciences, courses AND lectures.
• Adding a wildcard symbol may retrieve word variants: ((((international centre) or (international case))) or (international congress)) for mechanical sciences, courses and lectures*.