Perhaps you should try some spelling variations:
hieu nganh » hiem ngan, hieu manh, nghiep nganh
vien nganh » vien thanh
hanh trang » thanh trung, canh tranh, hanh trinh
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
trang va » tran van, hang va
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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 nganh)) - hanh trang va ((nhung cong) OR (thong cong)) dan than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu nganh) OR (vien nganh)) - hanh trang va ((nhung cong) OR (thong cong)) dan than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu nganh) or (vien nganh)) - hanh trang va ((nhung cong) OR (thong cong)) dan than cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu nganh) or (vien nganh)) - hanh trang va ((nhung cong) OR (thong cong)) dan than cao*.