Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
thu sach » tu sach, thuat sach, thuoc sach
hanh dai » hanh tai, hanh dao, vanh dai
cham tuc » nham thuc, tham thuc, cham soc
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
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: thu sach ky ((nang xa) or (nang ma)) hoi. hieu ve ((cham tuc) OR (pham thuc)) va hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((nang xa) OR (nang ma)) hoi. hieu ve ((cham tuc) OR (pham thuc)) va hanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky ((nang xa) or (nang ma)) hoi. hieu ve ((cham tuc) OR (pham thuc)) va hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((nang xa) or (nang ma)) hoi. hieu ve ((cham tuc) OR (pham thuc)) va hanh dai cua tre*.