Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
tang van » dang van, hoang van, trong van
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan doan » dan toan, tan doan, van doan
doan van » doan va, hoang van, luan van
tang ma » mang may
hieu he » hieu ve, hiem he, hieu le
van cua » vang cua, ban cua, dan cua
he nam » ha nam, nghe nam
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 y ((tang ma) or (tang van)) hoa. hieu he nam thuc dan doan van cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((tang ma) OR (tang van)) hoa. hieu he nam thuc dan doan van cua te.
• Adding a wildcard symbol may retrieve word variants: thu sach y ((tang ma) or (tang van)) hoa. hieu he nam thuc dan doan van cua te*.