Akademik

работать над собой
РАБОТАТЬ НАД СОБОЙ{{}}
[VP; subj: human; usu. this WO]
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to try to better o.s. in some area (by adding to one's credentials, furthering one's education etc):
- X работает над собой{{}} X is improving (trying to improve) himself;
- X is working (hard) at self-improvement;
- X is broadening his horizons.
     ♦ "Желание работать над собой и постоянное воспоминание о вас, фрейлейн Мари, не покидают меня..." (Федин 1). "The desire to improve myself, and the constant memory of you, Fraulein Marie, never leave me .." (1a).

Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. . 2004.