Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithm" » "modified multiobjective optimization algorithms", "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms"
"modified invasive estimation algorithm" » "modified invasive ventilation algorithm", "modified passive estimation algorithm"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified multiobjective optimization algorithm") OR ("modified invasive estimation algorithm"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified multiobjective optimization algorithm\") OR (\"modified invasive estimation algorithm\"))*".
• Removing quotes may allow a broader search: (( modified multiobjective optimization algorithm ) OR ( modified invasive estimation algorithm ))*.