Perhaps you should try some spelling variations:
optimisation algorithm » optimization algorithms, estimation algorithm, estimation algorithms
source algorithm » our algorithm, search algorithm
using source » using force, using morse
modified qoe » modified male, modified _, modified df
modified bi1 » modified _
code » core

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: (( code using source algorithm ) OR ( ((modified qoe) OR (modified bi1)) optimisation algorithm ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( code using source algorithm ) or ( ((modified qoe) OR (modified bi1)) optimisation algorithm ))~".
• Adding a wildcard symbol may retrieve word variants: (( code using source algorithm ) or ( ((modified qoe) OR (modified bi1)) optimisation algorithm ))*.