Perhaps you should try some spelling variations:
"modified objective estimation algorithms" » "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective approximation algorithms", "modified objective allocation algorithms"
"mobile learning estimation algorithm" » "mobile learning emotion algorithm", "mobile lighting estimation algorithm", "machine learning estimation algorithm"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified objective estimation algorithms\") OR (\"mobile learning estimation algorithm\"))~".
• Removing quotes may allow a broader search: (( modified objective estimation algorithms ) OR ( mobile learning estimation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified objective estimation algorithms") OR ("mobile learning estimation algorithm"))*.