Perhaps you should try some spelling variations:
naturalistic approach » heuristic approach, realistic approach, humanistic approach
pluralistic approach » pluralist approach, heuristic approach, realistic approach
futuristic approach » heuristic approach, humanistic approach, metaheuristic approach

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: ((((naturalistic approach) OR (pluralistic approach))) OR (futuristic approach)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((naturalistic approach) OR (pluralistic approach))) or (futuristic approach))".
• Adding a wildcard symbol may retrieve word variants: ((((naturalistic approach) OR (pluralistic approach))) or (futuristic approach))*.