Perhaps you should try some spelling variations:
"cost of _ healthy diets" » "cost of _ healthy city"
"cost of _ health diet" » "cost of _ health dietary", "cost of _ healthful diet", "cost of _ unhealthy diet"
"cost of _ healthy adults" » "cost of _ healthy adult"

Try widening your search to All Fields.

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: (((("cost of _ healthy diets") OR ((("cost of _ healthy diet") OR ("cost of _ health diet"))))) OR ("cost of _ healthy adults")).
• Removing quotes may allow a broader search: (((( cost of _ healthy diets ) or ((( cost of _ healthy diet ) or ( cost of _ health diet ))))) or ( cost of _ healthy adults )).
• Adding a wildcard symbol may retrieve word variants: (((("cost of _ healthy diets") or ((("cost of _ healthy diet") or ("cost of _ health diet"))))) or ("cost of _ healthy adults"))*.