Perhaps you should try some spelling variations:
vang nguyen » dang nguyen, van nguyen, sang nguyen
thanh trung » thanh tung
nhung cong » dung cong, thong cong, hang cong
hien xanh » hien nhanh, chieu xanh, hien khanh
hien hanh » dieu hanh
cong vang » cong lang, cong quang, cong ngang
trung va » truong va, trang va, trung ha

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien xanh) or (hien hanh)) - thanh trung va nhung cong vang nguyen van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (hien hanh)) - thanh trung va nhung cong vang nguyen van.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (hien hanh)) - thanh trung va nhung cong vang nguyen van*.