Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
truong va » truong dai, truong cao, truong dao
nang cong » nang song, dang cong, bang cong
ho chieu » theo chieu, hoc thieu, mot chieu
trang va » tran van, hang va
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan tap » toan ban

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 (doi chieu)) sach - thanh ((trang va) or (truong va)) nang cong dan toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) sach - thanh ((trang va) OR (truong va)) nang cong dan toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (doi chieu)) sach - thanh ((trang va) or (truong va)) nang cong dan toan tap".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (doi chieu)) sach - thanh ((trang va) or (truong va)) nang cong dan toan tap*.