Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, pham thu
nham thuc » nhan thuc, nam thuc, nham thu
thu sach » tu sach, thuat sach, thuoc sach
vat hanh » vat thanh, van hanh, va hanh
sach ky » sac ky, sach y, sach ty
nang co » nang doc, nang noi, nang hoc
hieu ve » hieu va, hieu van
hanh di » hanh vi, hanh de, hang di
di cua » dai cua, doi cua, de cua
cua te » cua tu

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 co) or (nang cao)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((nang co) OR (nang cao)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky ((nang co) or (nang cao)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh di cua te".
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((nang co) or (nang cao)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh di cua te*.