Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach tham » sach nha
sach thu » sach thue, sach thieu, cach thuc
danh vai » danh sai, danh va, doanh van
nang mai » nang ma, nang tai, lang mai
vai cua » dai cua, hai cua, lai cua
mai hoi » mai khoi, dai hoi, lai hoi
qua cao » qua cac, qua ca, qua cai
suc va » duc va, tuc va, soc va
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach thu) or (sach tham)) nang mai hoi. hieu qua cao ((suc va) OR (luc va)) danh vai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach thu) OR (sach tham)) nang mai hoi. hieu qua cao ((suc va) OR (luc va)) danh vai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach thu) or (sach tham)) nang mai hoi. hieu qua cao ((suc va) OR (luc va)) danh vai cua triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach thu) or (sach tham)) nang mai hoi. hieu qua cao ((suc va) OR (luc va)) danh vai cua triet*.