Perhaps you should try some spelling variations:
hoc thieu » toc thieu, hoc hien
tuong qua » tuong quan, thong qua, trong qua
dung cong » dung trong
ho chieu » theo chieu, doi chieu, mot chieu
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: ((ho chieu) or (hoc thieu)) xanh - thanh ((tuong qua) OR (duong qua)) dung cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) xanh - thanh ((tuong qua) OR (duong qua)) dung cong tac toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (hoc thieu)) xanh - thanh ((tuong qua) OR (duong qua)) dung cong tac toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (hoc thieu)) xanh - thanh ((tuong qua) OR (duong qua)) dung cong tac toan cau*.