Perhaps you should try some spelling variations:
significantly improves » significantly improved (Expand Search), significantly improve (Expand Search), significantly improving (Expand Search)
significantly smaller » significantly higher (Expand Search), significantly lower (Expand Search), significantly greater (Expand Search)
improves decrease » improves disease (Expand Search), improve disease (Expand Search), improved urease (Expand Search)
smaller decrease » small decrease (Expand Search), marked decrease (Expand Search), smaller areas (Expand Search)

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

• Removing quotes may allow a broader search: (( significantly smaller decrease ) OR ( significantly improves decrease ))*.