Perhaps you should try some spelling variations:
theo chieu » theo tieu, theo chu, thi chieu
hoc thieu » toc thieu, hoc hien
hanh tang » hanh trang, anh tang, hanh mang
dung cong » dung trong
ho chieu » doi chieu, mot chieu, thi chieu
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cao » toan ban, toan tap
tang su » tang suc, trang su, dang su

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (((ho chieu) OR (hoc thieu)))) sach - hanh tang su dung cong tap toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((theo chieu) or (((ho chieu) OR (hoc thieu)))) sach - hanh tang su dung cong tap toan cao~".
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) or (((ho chieu) OR (hoc thieu)))) sach - hanh tang su dung cong tap toan cao*.