Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
pham thuc » phap thuc, pham chuc, pham thu
sach thu » sach thue, sach thieu, sach tham
vat hanh » vat thanh, van hanh, va hanh
co sach » bo sach, cuon sach, hoc sach
sang ma » tang ma, nang ma, sang tao
hieu ve » hieu va, hieu van
vi cua » vai cua, di 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: co sach thu ((nang cao) or (sang ma)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach thu ((nang cao) OR (sang ma)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach thu ((nang cao) or (sang ma)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: co sach thu ((nang cao) or (sang ma)) hoi. hieu ve ((pham thuc) OR (nham thuc)) vat hanh vi cua te*.