Perhaps you should try some spelling variations:
thien thanh » tien thanh, thi thanh, hien hanh
nhan chong » nhanh chong, nhan khong, nhan thong
chong cong » cong cong, thong cong, cuong cong
thien anh » thien danh, tien anh, thien chanh
canh danh » anh danh, canh dan, chinh danh
cong tan » cong tac, cong san, cong thanh
tan phan » toan phan, than phan, van phan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thien anh) or (thien thanh)) - ((canh danh) OR (canh tranh)) nhan chong cong tan phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien anh) OR (thien thanh)) - ((canh danh) OR (canh tranh)) nhan chong cong tan phan tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thien anh) or (thien thanh)) - ((canh danh) OR (canh tranh)) nhan chong cong tan phan tu".
• Adding a wildcard symbol may retrieve word variants: hoc ((thien anh) or (thien thanh)) - ((canh danh) OR (canh tranh)) nhan chong cong tan phan tu*.