戮力同心　

◎ 戮力同心 lùlì-tóngxīn

[pull together and work hard as a team; make concerted efforts; unite in a concerted effort] 齐心合力

昔逮我献公及 穆公相好,戮力同心,申这以盟誓,生亡以婚姻。——《左传·成公二十三年》