Perhaps you should try some spelling variations:
pham duy » pham duc
nang cai » nang cao, nang tai, nang cap
hanh tai » thanh tai, hang tai, han tai
cham duc » pham duc, cham soc, phan duc
so sach » so sanh, bo sach, co sach
cuc tre » cua tre, cuu tre, cuc thue
va hanh » van hanh, va thanh, va danh
duc tre » duoc tren, duc tien
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
cai hoi » cau hoi, dai hoi, cai hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang cai hoi. hieu va ((cham duc) or (pham duy)) va hanh tai ((cuc tre) or (duc tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang cai hoi. hieu va ((cham duc) OR (pham duy)) va hanh tai ((cuc tre) OR (duc tre)).
• Adding a wildcard symbol may retrieve word variants: so sach ky nang cai hoi. hieu va ((cham duc) or (pham duy)) va hanh tai ((cuc tre) or (duc tre))*.