Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
day hanh » day nhanh, day thanh, dao hanh
sach thu » sach thue, sach thieu, sach tham
nang noi » nang doc
nam thuc » nam thuoc, am thuc, nam thu
hanh di » hanh vi, hanh de, hang di
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, xach tay
noi hoi » noi doi, doi hoi, hoi hoi
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: tu ((sach ty) or (sach thu)) nang noi hoi. hieu ve ((pham thuc) or (nam thuc)) day hanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) nang noi hoi. hieu ve ((pham thuc) OR (nam thuc)) day hanh di cua te.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) nang noi hoi. hieu ve ((pham thuc) or (nam thuc)) day hanh di cua te*.