Canadian retail sales rebounded in January, but the advance was fueled by unusually strong demand for new motor vehicles, particularly small fuel-efficient cars. Retail sales rose 0.5 percent to C$38.9 billion in January, a fifth increase in six months, Statistics Canada reported Thursday. However, excluding sales at motor vehicle and parts dealers, retail sales declined 0.5 percent. Economists expected total retail sales to rise 1.8 percent, following a modest 0.2 percent decline in December. New car dealers were busy, posting their highest monthly growth rate in three years. Sales of new vehicles were up 4.6 percent. Supermarkets and grocery store sales were down 0.9 percent, while home improvement store sales slipped 5.2 percent. Electronics and appliance stores registered a sales decline of 3.4 percent, down for a third month in a row.