Perhaps you should try some spelling variations:
"modified multiobjective approximation algorithms" » "modified multiobjective optimization algorithms"
"model using metal algorithm" » "code using metal algorithm", "models nursing metal algorithm", "powder using metal algorithm", "model using real algorithm", "model nursing mental algorithm", "model using medical algorithm"

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: (("model using metal algorithm") OR ("modified multiobjective approximation algorithms"))~.
• Removing quotes may allow a broader search: (( model using metal algorithm ) or ( modified multiobjective approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("model using metal algorithm") or ("modified multiobjective approximation algorithms"))*.