Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
pham thuc » phap thuc, pham chuc, nham thuc
doc sach » hoc sach, toc sach, nuoc sach
hanh lai » hanh lam, hanh tai, thanh lap
va trien » va truyen, va thiet, va tuyen
tang ma » mang may, tang van
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
nang ma » sang ma, nang cao, mang may
ve pham » vi pham, v pham, ve phan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky ((nang ma) OR (tang ma)) hoi. hieu ve pham thuc va hanh lai ((cua triet) or (va trien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ky ((nang ma) OR (tang ma)) hoi. hieu ve pham thuc va hanh lai ((cua triet) OR (va trien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ky ((nang ma) OR (tang ma)) hoi. hieu ve pham thuc va hanh lai ((cua triet) or (va trien))".
• Adding a wildcard symbol may retrieve word variants: doc sach ky ((nang ma) OR (tang ma)) hoi. hieu ve pham thuc va hanh lai ((cua triet) or (va trien))*.