Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh doi » thanh doi, hanh noi, hang doi
tham duc » pham duc, tham du, than duc
va tham » van tham, va cham, va thanh
cua tre » cua te, cuu tre, dua tren
va hanh » van hanh, va thanh, va danh
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
lang ha » long ha
hieu va » lieu va, hieu qua

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 tu ((nang x) or (lang ha)) hoi. hieu va tham duc va hanh doi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu ((nang x) OR (lang ha)) hoi. hieu va tham duc va hanh doi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tu ((nang x) or (lang ha)) hoi. hieu va tham duc va hanh doi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: te sach tu ((nang x) or (lang ha)) hoi. hieu va tham duc va hanh doi ((cua tre) OR (cua triet))*.