Perhaps you should try some spelling variations:
international congress » international conference
international context » international conference
international centre » international theatre, international case, international capital
mechanical sciences » technical sciences, mechanical stresses, clinical sciences
mechanical science » mechanism science, clinical science, mechanical stretch
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 context) OR (international congress)))) for ((mechanical sciences) OR (mechanical science)), courses AND lectures.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((international centre) or (((international context) or (international congress)))) for ((mechanical sciences) OR (mechanical science)), courses and lectures".
• Adding a wildcard symbol may retrieve word variants: ((international centre) or (((international context) or (international congress)))) for ((mechanical sciences) OR (mechanical science)), courses and lectures*.