Perhaps you should try some spelling variations:
significant improvements » significant improvement (Expand Search)
significantly increased » significant increase (Expand Search)
improvements decrease » improvements increased (Expand Search), improvements across (Expand Search)
increased decrease » increased release (Expand Search), increased crash (Expand Search)

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

• Removing quotes may allow a broader search: (( significantly increased decrease ) OR ( significant improvements decrease ))~.