Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cua tre » cua te, cuu tre, dua tren
hanh le » thanh le, hanh ve, hanh de
sach ky » sac ky, sach y, sach ty
te sach » toc sach
va chat » van chat, va phat, cao chat
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
loc va » luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang ma hoi. hieu va chat ((loc va) OR (hoc va)) hanh le ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ma hoi. hieu va chat ((loc va) OR (hoc va)) hanh le ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ma hoi. hieu va chat ((loc va) OR (hoc va)) hanh le ((cua tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ma hoi. hieu va chat ((loc va) OR (hoc va)) hanh le ((cua tre) or (cua triet))*.