Perhaps you should try some spelling variations:
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
invasive estimation » invasive ventilation
objective solution » objective evolutionary, objective allocation
solution algorithm » evolution algorithm, convolution algorithms, evolutionary algorithm
modified invasive » modified passive

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