Complex sentence: During the 1970s and even in 1989 there were some attempts to pick up the Stechovice treasure under the control of the Ministries of Interior and Defence, the last works had been done before the Revolution by the foreign trade company Omnipol, trading mainly with weapons.
Split into simpler sentences: During the 1970s, and even in 1989, there were some attempts to pick up the Stechovice treasure under the control of the Ministries of Interior and Defence. The last works had been done before the Revolution by the foreign trade company Omnipol, trading mainly with weapons.