Sang, who is on a visit to Singapore and Malaysia visit between September 26 and 30, said Malaysia was one of Vietnam's leading trade and investment partners.
Bilateral trade was worth US$5.5 billion last year and Malaysia has pledged investment of $19 billion in Vietnam.
Discussing the East Sea, the two leaders agreed that all concerned parties need to obey the 1982 UN Convention on the Law of the Sea and strictly implement the Declaration on the Conduct of Parties in the East Sea and work toward building the Code of Conduct.
Earlier the same day, Sang met Singaporean Prime Minister Lee Hsien Loong on the last day of his visit to the island nation.
The two leaders witnessed the signing of an agreement to build an industrial zone in Vietnam's Quang Ngai Province between the Quang Ngai People's Committee and Vietnam Singapore Industrial Park JV Co Ltd.
The previous day, Sang had met Singaporean business leaders and expressed his desire that more would come to Vietnam.
He also attended the unveiling of President Ho Chi Minh's statue at the Asian Civilizations Museum.