Perhaps you should try some spelling variations:
dam thuc » am thuc, dan thuc, nam thuc
cua viet » hoa viet, cua vat, cua dieu
sang mai » sang ma, sang tai, lang mai
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
ca viet » va viet, co viet, hoa viet
cam tu » cam thu, nam tu, dam tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky sang mai hoi. hieu ve ((dam thuc) or (cam tu)) va hanh vi ((cua viet) or (ca viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky sang mai hoi. hieu ve ((dam thuc) OR (cam tu)) va hanh vi ((cua viet) OR (ca viet)).
• Adding a wildcard symbol may retrieve word variants: su sach ky sang mai hoi. hieu ve ((dam thuc) or (cam tu)) va hanh vi ((cua viet) or (ca viet))*.