pull/haul yourself up by your bootstrapsIMPROVEto improve your position and get out of a difficult situation by your own efforts, without help from other people 自力更生〔改善境遇、摆脱困境〕
Originbootstraps
(1900-2000)bootstrap“piece of leather or cloth attached to the back of a boot to make it easier to pull on”((19-20 centuries))