Perhaps you should try some spelling variations:
"modified topology estimation algorithms" » "modified topology estimation algorithm", "modified topology optimization algorithms", "modified topology optimisation algorithm"
"modified invasive approximation algorithms" » "modified passive approximation algorithms"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified topology estimation algorithms") OR ("modified invasive approximation algorithms"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified topology estimation algorithms\") OR (\"modified invasive approximation algorithms\"))".
• Removing quotes may allow a broader search: (( modified topology estimation algorithms ) OR ( modified invasive approximation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (("modified topology estimation algorithms") OR ("modified invasive approximation algorithms"))*.