Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
vien thanh » viet thanh, tien thanh, dien thanh
canh trinh » canh tranh, hanh trinh, canh tinh
nhung cong » dung cong, thong cong, hang cong
cong tinh » cong trinh, cong vinh, long tinh
trinh va » trinh van, trinh vat, trinh ve
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu nganh) or (vien thanh)) - canh trinh va nhung cong tinh toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu nganh) OR (vien thanh)) - canh trinh va nhung cong tinh toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu nganh) or (vien thanh)) - canh trinh va nhung cong tinh toan cao*.