Perhaps you should try some spelling variations:
extended theory » extended memory, extension theory
bounded theory » grounded theory, bounds theory, bounded theories
blended theory » blending theory, blended query, blended shore

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: ((bounded theory) OR (((blended theory) OR (extended theory)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((bounded theory) or (((blended theory) OR (extended theory))))".
• Adding a wildcard symbol may retrieve word variants: ((bounded theory) or (((blended theory) OR (extended theory))))*.