Perhaps you should try some spelling variations:
"materials optimization" » "criteria optimization", "models optimization", "mathematical optimization"
"material optimization" » "numerical optimization", "criteria optimization", "mathematical optimization"
"automatic estimation" » "automatic optimization", "automatic extraction", "automatic evaluation"

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: (((("materials optimization") OR ("material optimization"))) OR ("automatic estimation")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"materials optimization\") OR (\"material optimization\"))) or (\"automatic estimation\"))".
• Removing quotes may allow a broader search: (((( materials optimization ) OR ( material optimization ))) or ( automatic estimation )).
• Adding a wildcard symbol may retrieve word variants: (((("materials optimization") OR ("material optimization"))) or ("automatic estimation"))*.