Perhaps you should try some spelling variations:
improv\ » improve\ (Expand Search), improved\ (Expand Search)
improvee\ » improveee\ (Expand Search), improvedee\ (Expand Search), improve\ (Expand Search), improved\ (Expand Search)
improvedee\ » improveedee\ (Expand Search), improvededee\ (Expand Search), improved\ (Expand Search)
improvedde » improveedde (Expand Search), improvededde (Expand Search), improved (Expand Search)
improveed » improveeed (Expand Search), improvedeed (Expand Search), improved (Expand Search), improvedd (Expand Search), improve (Expand Search)

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((\ theatre improv\ ) OR (\ theatre (((improvee\ OR improvedee\) OR improvedde ) OR improveed )))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\ theatre improv\ ) OR (\ theatre (((improvee\ OR improvedee\) OR improvedde ) OR improveed )))".
• Adding a wildcard symbol may retrieve word variants: ((\ theatre improv\ ) OR (\ theatre (((improvee\ OR improvedee\) OR improvedde ) OR improveed )))*.