Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
nang mai » nang ma, nang tai, lang mai
hanh dai » hanh tai, hanh dao, vanh dai
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, dua tren
y nang » ky nang, ly nang, v nang
ve cam » ve cham, ve cac, va cam
luc 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: tu sach y nang mai hoi. hieu ve cam ((luc va) or (duc va)) hanh dai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang mai hoi. hieu ve cam ((luc va) OR (duc va)) hanh dai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang mai hoi. hieu ve cam ((luc va) or (duc va)) hanh dai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang mai hoi. hieu ve cam ((luc va) or (duc va)) hanh dai ((cua tre) OR (cua triet))*.