Bulgaria's fast-track economy feels a drag from old austere policies

Floor by floor, Sofia's TSUM department store offers a wide range of goods from textiles to electronics. With some exceptions, the items are sold at prices suited even to modest pocketbooks.

Bulgarian living standards are comparable to the better levels in the East bloc as a whole and better than those in Romania, Bulgaria's next-door neighbor.

While leaders of this hardworking, underdeveloped Balkan nation remind visitors that Bulgaria's economic growth has been faster than that of any of its communist allies, they also admit there is standstill - and even downturn - in some crucial sectors. The ''new economic mechanism,'' established four years ago , is held back by remnants of an austere, Soviet-style economic past.

Both politicians and economists here seem aware that structural changes introduced in 1980 were not deep enough to make a clean break with an economic system laden with bottlenecks and bureaucratic impediments to good management. Even behind the apparently plentiful consumer scene there are problems of shortages.

''Just now,'' says a Sofia acquaintance, ''there's no yogurt,'' which is serious in a country that claims to have discovered it. Such shortages are usually matters of faulty local distribution and thus are unlike the virtually permanent shortages in Poland and Romania.

Bulgaria's essential problem is not so much maintaining an adequate supply of goods as it is meeting growing demands for quality, from both the domestic customer and the export buyer.

President Todor Zhivkov has been warning that Bulgaria is losing part of its Western market by failing to turn out products that can compete with Western goods. He made it clear that the country's alliance partners and the ordinary domestic consumer were dissatisfied with the quality of many Bulgarian-made items.

A serious deficiency is in electronics, in which this country has previously had marked sales success in the West. Bulgaria is allotted a special role in the so-called ''division of labor'' in the East bloc's ''common market.''

For two years, progress in valuable areas of Western export - notably in machinery - has slowed. To make matters worse, Western trade barriers compel Bulgaria to sell farm products, recognized as among the best in Europe, at lower prices than other growers command.

In a new focus on the country's economic shortcomings, the Communist Party daily Rabotnichesko Delo recently ran an article entitled ''For higher quality, for a new approach and serious responsibility.'' Management is being warned that quality and regard for consumer needs must come first if enterprises are to avoid stiff sanctions for substandard performance and to qualify for investment credits and incentives.

Efforts are afoot to stimulate research and acquire technology. Bulgaria already uses know-how from the United States, Western Europe, and Japan in agriculture and industry. Several years of experimentation in production of American corn have shown excellent results. Now nearly two-thirds of maize grown here comes from this new technology.

More industries operate under strict quality controls. A Japanese-like system of management and worker cooperation to improve production is popular. Notes Prof. Vassil Mischev of the Academy of Public and Social Science Management: ''I agree with Japan. The countries that advance quickest are not necessarily those inventing the new technology, but those that use it.''