Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
sach thu » sach thue, sach thieu, sach tham
cham hoi » cham voi, cham h'roi, pham hoai
sach tu » cach tu, sach ty, sach uu
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
tang ma » mang may, tang van
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
cam lo » nam lo, cam ly, cam o

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((sach tu) OR (sach thu)) tang ma hoi. hieu ve ((cham hoi) or (cam lo)) va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach tu) OR (sach thu)) tang ma hoi. hieu ve ((cham hoi) OR (cam lo)) va hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach tu) OR (sach thu)) tang ma hoi. hieu ve ((cham hoi) or (cam lo)) va hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach tu) OR (sach thu)) tang ma hoi. hieu ve ((cham hoi) or (cam lo)) va hanh vai cua tre*.