收复 is specifically about regaining lost territory or land. Common collocations: 收复失地 (recover lost territory), 收复领土 (reclaim territory). Don't confuse with 恢复 (huīfù, to restore/resume) which is more general.
history
收复 frequently appears in Chinese history lessons, especially regarding: 收复台湾 (Zheng Chenggong recovering Taiwan from the Dutch, 1662) and 收复新疆 (Zuo Zongtang recovering Xinjiang, 1870s).