Perhaps you should try some spelling variations:
approximation algorithm » approximation algorithms
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
objective estimation » objective optimization, objective allocation
seird approximation » time approximation, network approximation
modified seird » modified near

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

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