Four Cambodian high school students won prizes in the Southeast Asian Mathematics Olympiad held in Malaysia, education officials said. Chea Vaddnak a 12 grader from Phnom Penh, won a silver medal in the regional competition. Heng Salpisith and Leng Vandy, from Pursat, and Each Setha from Takeo all won bronze medals, said En Kimsrun of the Education Ministry. `We are not weak We will prepare our students for the world mathematics competition," En Kimsrun said, though he noted that the country lacks the budget and teachers to ad-quately train students for the world match. He said the ministry would like to select 50 junior high school students from across the country who do well in math, train them for three years and select four for the match, which occurs annually. Cambodian students won two bronze medals in regional competition three years ago.