Perhaps you should try some spelling variations:
optimization model » optimization models, optimization based, optimization problem
model developing » models developing, model development, done developing
solving problems » solvency problems
housing problems » housing programs, housing projects, housing project
prices » price

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

• Performing a fuzzy search may retrieve terms with similar spellings: optimization model developing ((solving problems) or (((housing problems) OR (housing prices)))).~.
• If you are trying to use Boolean operators, they must be ALL CAPS: optimization model developing ((solving problems) OR (((housing problems) OR (housing prices)))).*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "optimization model developing ((solving problems) or (((housing problems) OR (housing prices)))).*".