Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu manh » chieu xanh, hieu nganh, dieu hanh
canh tinh » canh tranh, nhanh tinh, thanh tinh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
manh tinh » man tinh, manh binh, nhanh tinh
hoc hieu » hoc thieu, hoc hien, doc hieu
cong tac » cong ty
tac phan » tac pham, tai phan, tac phat
phan lap » phan dau

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 manh - ((((canh tinh) OR (hanh tinh))) or (manh tinh)) va nhung cong tac phan lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - ((((canh tinh) OR (hanh tinh))) OR (manh tinh)) va nhung cong tac phan lap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu manh - ((((canh tinh) OR (hanh tinh))) or (manh tinh)) va nhung cong tac phan lap".
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - ((((canh tinh) OR (hanh tinh))) or (manh tinh)) va nhung cong tac phan lap*.