Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
ho chiet » ho chieu, ho thiet, hoa thiet
mang cua » manh cua, ban cua, cong cua
dung cua » dung luan, dung cho
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cau » 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: ((ho chiet) OR (hoc thiet)) tach - anh ((mang cua) or (dung cua)) nhung cong tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chiet) OR (hoc thiet)) tach - anh ((mang cua) OR (dung cua)) nhung cong tan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chiet) OR (hoc thiet)) tach - anh ((mang cua) or (dung cua)) nhung cong tan toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chiet) OR (hoc thiet)) tach - anh ((mang cua) or (dung cua)) nhung cong tan toan cau*.