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 model » modified male
model solution » model solutions, nodal solution, model selection

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

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