From any Quran or Hadith preview, you can initiate looking for verses similar to it. Hover the mouse over any preview (the target verse) to reveal its associated action buttons, then click on
How is similarity determined? Basically, the system determines the proportion of terms a verse shares with the target verse. If this exceeds the threhold value in Settings, it is considered similar.
Note that looking for verses similar to a Quran verse will only find other Quran verses. Similarly for Hadiths.
See the following video for an example of finding similar verses: