THE FOURTH GAME of the world championship chess match in New York between champion Garry Kasparov and Anatoly Karpov was adjourned until Thursday night in a position experts said would probably end in a draw . . . THE SALVADORAN ARMY Thursday drove off leftist guerrillas who attacked air force headquarters with homemade mortars and automatic weapons, and authorities said several people were wounded . . . A U.S. NAVY ship on routine duty rescued 50 Vietnamese refugees aboard a crippled wooden boat in the South China Sea, a navy spokesman said Thursday.