Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
tong cong » trong cong, cong cong, dung cong
ho chieu » theo chieu, hoc thieu, mot chieu
tranh va » tranh van, trang va, thanh va
trinh va » trinh van, trinh vat, trinh ve
cong dan » cong san, cong tan, huong dan
dan phan » doan phan, dan chan, van phan
phan cac » nhan cach, phan dau, phan lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) OR (ho chieu)) sach - canh ((tranh va) or (trinh va)) tong cong dan phan cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (ho chieu)) sach - canh ((tranh va) OR (trinh va)) tong cong dan phan cac.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (ho chieu)) sach - canh ((tranh va) or (trinh va)) tong cong dan phan cac".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (ho chieu)) sach - canh ((tranh va) or (trinh va)) tong cong dan phan cac*.