poignancy       
noun [ U ] uk/ˈpɔɪ.njən.si/ us/ˈpɔɪ.njən.si/
 辛酸
the quality of causing or having a very sharp feeling of sadness
  The production took on added poignancy due to the director's recent death.
 The poem has a haunting poignancy. 这首诗有一种令人难以忘怀的凄凉。 
 See: poignant
 - More examples
 - She begins to question, with great poignancy, what her son's sacrifice was for.
 - There are many moments of almost unbearable poignancy in the film.
 - Even his faltering memory was a source of poignancy.