原来悲伤也狠难掩盖原来幸福也可以伪装
[yuán lái bēi shāng yĕ hĕn nán yăn gài yuán lái xìng fú yĕ kĕ yĭ wĕi zhuāng]
It conveys deep introspection about feelings: that sadness is hard to hide, and that happiness may sometimes just be pretense. The owner may have hidden sorrow behind a facade of joy.