FROM faraway Riau, the news came as a blow. Thousands of historical Malay documents more than a century old have been whisked away to neighboring countries: Singapore, Brunei and Malaysia. This has been going on for the past 20 years. One by one, the ownership of the documents has changed: antique letters from the old kingdoms on the Sumatran coast, hand-written copies of the Quran, poems, verses and records of a high degree of civilization of Ri