Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
tong huong » thong huong, tong thuong, cong huong
trinh han » trinh quan
huong van » huong dan, duong van, hong van
trinh ha » trinh hoa, trinh nha, trinh he
van than » van thanh, van thang, van tuan
than cau » toan cau, phan cau, 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: doc ((dieu hanh) or (hieu nganh)) - hanh ((trinh ha) or (trinh han)) tong huong van than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((dieu hanh) OR (hieu nganh)) - hanh ((trinh ha) OR (trinh han)) tong huong van than cau.
• Adding a wildcard symbol may retrieve word variants: doc ((dieu hanh) or (hieu nganh)) - hanh ((trinh ha) or (trinh han)) tong huong van than cau*.