Perhaps you should try some spelling variations:
phuong cong » phuong dong, phong cong, phung cong
theo chieu » theo tieu, ho chieu, theo chu
chieu sang » chieu sach, chieu xanh, hieu lang
thang va » hang va, trang va, thanh va
thong va » thong cua, truong va, thong qua
cong tac » cong ty
tac toan » tap toan, tam toan, hach 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: theo chieu sang - hanh ((thang va) OR (thong va)) phuong cong tac toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu sang - hanh ((thang va) OR (thong va)) phuong cong tac toan cau*".