Perhaps you should try some spelling variations:
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
objective estimation » objective optimization, objective allocation
solution algorithm » evolution algorithm, convolution algorithms, evolutionary algorithm
modified passive » modified adaptive
passive solution » positive solutions, saline solution

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( modified objective estimation algorithms ) OR ( modified passive solution algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (( modified objective estimation algorithms ) or ( modified passive solution algorithm ))*.