Perhaps you should try some spelling variations:
significantly smaller » significantly higher (Expand Search), significantly lower (Expand Search), significantly greater (Expand Search)
significantly weaker » significantly greater (Expand Search), significantly better (Expand Search), significantly related (Expand Search)
smaller decrease » small decrease (Expand Search), marked decrease (Expand Search), smaller areas (Expand Search)
weaker decrease » greater decrease (Expand Search), teer decrease (Expand Search), water decreases (Expand Search)

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

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