Perhaps you should try some spelling variations:
"modified adaptive optimization algorithms" » "modified adaptive optimisation algorithm", "modified adaptive estimation algorithms", "modified adaptive estimation algorithm", "modified objective optimization algorithms", "modified adaptive quantization algorithms", "modified static optimization algorithms", "modified passive optimization algorithms"
"modified df approximation algorithm" » "modified df approximation algorithms", "modified _ approximation algorithm", "modified one approximation algorithm", "modified time approximation algorithm", "modified adam approximation algorithm", "modified bi1 approximation algorithm"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified df approximation algorithm") or ("modified adaptive optimization algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified df approximation algorithm") OR ("modified adaptive optimization algorithms")).
• Removing quotes may allow a broader search: (( modified df approximation algorithm ) or ( modified adaptive optimization algorithms )).
• Adding a wildcard symbol may retrieve word variants: (("modified df approximation algorithm") or ("modified adaptive optimization algorithms"))*.