Vietnam earned over 3.5 billion U.S. dollars from exporting cashew nuts this year, up 20 percent over last year, while spending more than 2.5 billion U.S. dollars importing raw cashew, up 22 percent, Vietnamese Ministry of Agriculture and Rural Development said on Friday.Vietnam exported 352,205 tons of cashew nuts in 2017, mainly to the United States, the Netherlands and China, the ministry said. Meanwhile, Vietnam imported 1.1 million tons of raw cashew from Africa.Vietnam has strength in cashew processing and customer base and it will assist Cambodia, which is interested in expanding cashew-growing area and exporting raw cashew, in growing 500,000 hectares of cashew with output of some 1 million tons in the next 10 years, according to the Vietnam Cashew Association. Vietnam's cashew-growing area dropped to 290,000 hectares in 2015 from 440,000 hectares in 2007, according to the ministry. In 2016, the area increased by 5,600 hectares.