Perhaps you should try some spelling variations:
"modified changing optimization algorithms" » "modified changing optimisation algorithm", "modified changing estimation algorithms", "modified changing estimation algorithm", "modified staffing optimization algorithms", "modified caging optimization algorithms"
"modified static approximation algorithms" » "modified time approximation algorithms"

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: (("modified changing optimization algorithms") OR ("modified static approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified changing optimization algorithms ) or ( modified static approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified changing optimization algorithms") or ("modified static approximation algorithms"))*.