Does the Soviet Union have proposals about conceptual missions to Mercury and outer planets

I think that during the Cold War the Soviet Union may have drafted some conceptual proposals onsending their space probes to Mercury and the far outer planets like Uranus and beyond, but as I don't know Russian language so I would like to know that whether I'm correct that the CCCP has actually drafted the proposals about those conceptual missions, and if they did are those available online w. translation?
They had ambitious plans, but lack of Political interest, technical problems and lack of powerful rockets to do deep space Missions
While there Venera missions were successful, were there Mars missions always some kind of a total disaster...