Perhaps you should try some spelling variations:
trinh toan » tinh toan, thanh toan, trinh han
nhung cong » dung cong, thong cong, hang cong
trinh cua » tinh cua, trinh luat, trinh quan
hoi hieu » hoi phieu, hoi tieu, moi hieu
sinh cua » manh cua, dinh cuu, sinh va
toan cau » toan cao, toan ban, toan tap
ho hieu » ho chieu, nho hieu, co hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho hieu) or (hoi hieu)) lang - hanh ((sinh cua) or (trinh cua)) nhung cong trinh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho hieu) OR (hoi hieu)) lang - hanh ((sinh cua) OR (trinh cua)) nhung cong trinh toan cau.
• Adding a wildcard symbol may retrieve word variants: ((ho hieu) or (hoi hieu)) lang - hanh ((sinh cua) or (trinh cua)) nhung cong trinh toan cau*.