Perhaps you should try some spelling variations:
optimization algorithms » optimisation algorithm, estimation algorithms, estimation algorithm
df optimization » _ optimization, qoe optimization, _ optimisation
code nursing » code using, care nursing, models nursing
modified df » modified _, modified adam, modified bi1
methods » method

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "(( code nursing methods algorithm ) OR ( modified df optimization algorithms ))~".
• Adding a wildcard symbol may retrieve word variants: (( code nursing methods algorithm ) OR ( modified df optimization algorithms ))*.