Perhaps you should try some spelling variations:
khong cong » thong cong, khong cang, chong cong
hien xanh » hien nhanh, chieu xanh, hien khanh
hien hanh » dieu hanh
trinh hoa » trinh do
trinh han » trinh quan
cong tan » cong tac, cong san, cong thanh
tran tap » toan tap, tran tan, tran tuan

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)) - canh ((trinh hoa) or (trinh han)) khong cong tan tran tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (hien hanh)) - canh ((trinh hoa) OR (trinh han)) khong cong tan tran tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) OR (hien hanh)) - canh ((trinh hoa) or (trinh han)) khong cong tan tran tap*".