Perhaps you should try some spelling variations:
thanh trung » thanh tung
theo chieu » theo tieu, ho chieu, thi chieu
trung tac » trung tam, trong tac, trung tai
trong bai » trong ban, thong bai, trong hai
theo chu » cho chu, chao chu, theo yeu
tac dung » sach dung, xay dung, tin dung
bai toan » bai tap
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) or (theo chu)) sach - thanh trung tac dung trong bai toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (theo chu)) sach - thanh trung tac dung trong bai toan cau.
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) or (theo chu)) sach - thanh trung tac dung trong bai toan cau*.