Perhaps you should try some spelling variations:
sach tham » sach nha
nham thuc » nhan thuc, nam thuc, nham thu
hanh dai » hanh tai, hanh dao, vanh dai
vat hanh » vat thanh, van hanh, va hanh
sach thu » sach thue, sach thieu, cach thuc
ve nham » ve nha, ve cham
hieu ve » hieu va, hieu van
sang ma » tang ma, nang ma, sang tao
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: bo ((sach thu) or (sach tham)) ((nang cao) or (sang ma)) hoi. hieu ve nham thuc vat hanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo ((sach thu) OR (sach tham)) ((nang cao) OR (sang ma)) hoi. hieu ve nham thuc vat hanh dai cua te.
• Adding a wildcard symbol may retrieve word variants: bo ((sach thu) or (sach tham)) ((nang cao) or (sang ma)) hoi. hieu ve nham thuc vat hanh dai cua te*.