Perhaps you should try some spelling variations:
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
network estimation » network optimization
modified network » certified network, defined network, modified near
mobile learning » machine learning
from algorithm » mom algorithm, adam algorithm

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( mobile learning from algorithm ) or ( modified network estimation algorithms ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( mobile learning from algorithm ) OR ( modified network estimation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (( mobile learning from algorithm ) or ( modified network estimation algorithms ))*.