Perhaps you should try some spelling variations:
"bounded theory" » "bounds theory", "bounded theories", "grounded theory6"
"blended theory" » "extended theory", "blending theory", "blended query"
"ground theory" » "group theory", "groups theory", "grand theory"
"grounded theory" » "founded 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 ("ground theory"))) OR ((("bounded theory") OR ("blended theory")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"grounded theory\") OR (\"ground theory\"))) or (((\"bounded theory\") or (\"blended theory\"))))".
• Removing quotes may allow a broader search: (((( grounded theory ) OR ( ground theory ))) or ((( bounded theory ) or ( blended theory )))).
• Adding a wildcard symbol may retrieve word variants: (((("grounded theory") OR ("ground theory"))) or ((("bounded theory") or ("blended theory"))))*.