爽然若失 [－－－－]

Jyutping song2 jin4 joek6 sat1
Pinyin shuǎng rán ruò shī

Definitions (CC-CEDICT)
  1. at a loss
  2. confused
  3. not know what to do next
Definitions (Wiktionary)
  1. phrase, idiomatic
    to feel dejected and lost