( saying ) it is better to keep sth that you already have than to risk losing it by trying to get much more
A BIRD IN THE HAND IS WORTH TWO IN THE BUSH
Meaning of A BIRD IN THE HAND IS WORTH TWO IN THE BUSH in English
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005