Vitolinish vs. Tukmakov

I can't understand strategic, positional grandmaster chess. There seems to be a whole lot of chess left in that game. But to a grandmaster, it's already a resignable position. Mindboggling. 

Black is basically paralyzed in the final position. 34...Rb7 allows 35. Bh5 and 36. Qe8+, picking up the Bishop. Any Queen retreat simply allows White to pick up a second pawn and keep his attack while the Bishop is frozen because of mate. And 34...dxc4?? allows 35. Bxc6 and mate in a few moves.