Perhaps you should try some spelling variations:
thanh trung » thanh tung
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hoc thieu » toc thieu, hoc hien
trung cap » truong cao, trung tam
ho chieu » theo chieu, doi chieu, mot chieu
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: ((ho chieu) or (hoc thieu)) sach - thanh trung cap ((nhung cong) OR (thong cong)) bai toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) sach - thanh trung cap ((nhung cong) OR (thong cong)) bai toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (hoc thieu)) sach - thanh trung cap ((nhung cong) OR (thong cong)) bai toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (hoc thieu)) sach - thanh trung cap ((nhung cong) OR (thong cong)) bai toan cau*.