偏劳

偏勞
piānláo
  1. undue trouble
  2. Thank you for having gone out of your way to help me.

CEDICT

to give someone undue trouble (used when asking somebody for help or thanking somebody for his help)

Wiktionary

请人帮忙或谢人代替自己做事的谦词。

重編國語辭典

Entry Composition

1 偏 piān
  1. to lean
  2. to slant
  3. oblique
  4. prejudiced
  5. to deviate from average
  6. to stray from the intended line
  7. stubbornly
  8. contrary to expectations
2 劳 láo
  1. (bound form) to toil; labor
  2. (bound form) laborer
  3. (bound form) meritorious deed
  4. (bound form) fatigue
  5. to put sb to the trouble (of doing sth)
  6. to express one's appreciation (Taiwan pr. lào)