Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh vai » hanh vi, hanh va, hanh tai
cam thuc » nam thuc, cam thu, can thuc
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach kem
danh ma » anh ma, danh ca, hanh ma
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet

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) OR (sach ty)) danh ma hoa. hieu van ((cam thuc) or (am thuc)) va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach ty)) danh ma hoa. hieu van ((cam thuc) OR (am thuc)) va hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) OR (sach ty)) danh ma hoa. hieu van ((cam thuc) or (am thuc)) va hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) OR (sach ty)) danh ma hoa. hieu van ((cam thuc) or (am thuc)) va hanh vai cua tre*.