Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hoc sach » hoc sinh, hoc cac, hoc anh
thanh ca » thanh cha, thanh cac, thanh ha
cao hoc » co hoc, cho hoc, chat hoc
hieu va » lieu va, hieu qua
duoc va » duc va, duoc ma, duong va
cua tre » cua te, cuu tre, dua tren
y nang » ky nang, ly nang, v nang
va nam » van nam, ha nam, va nay

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach y nang cao hoc. hieu va nam ((duoc va) or (nuoc va)) thanh ca ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach y nang cao hoc. hieu va nam ((duoc va) OR (nuoc va)) thanh ca ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach y nang cao hoc. hieu va nam ((duoc va) or (nuoc va)) thanh ca ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: hoc sach y nang cao hoc. hieu va nam ((duoc va) or (nuoc va)) thanh ca ((cua tre) OR (cua triet))*.