Perhaps you should try some spelling variations:
"founded theory" » "grounded theory6", "founding theory", "coupled theory"
"grand theory" » "graph theory", "band theory", "grand theories"
"grounded theory" » "ground theory", "bounded theory"

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: (((("grounded theory") OR ("grand theory"))) OR ("founded theory")).
• Removing quotes may allow a broader search: (((( grounded theory ) or ( grand theory ))) or ( founded theory )).
• Adding a wildcard symbol may retrieve word variants: (((("grounded theory") or ("grand theory"))) or ("founded theory"))*.