Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hieu he » hieu ve, hiem he, hieu le
dan dan » dang dan, ban dan, dao dan
he nam » ha nam, nghe nam
x hoi » xa hoi, o hoi, x ho
ca tu » cau tu, ca thu, cac tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang x hoi. hieu he nam thuc dan dan ((ca tu) or (ca tru)) tieng~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang x hoi. hieu he nam thuc dan dan ((ca tu) OR (ca tru)) tieng.
• Adding a wildcard symbol may retrieve word variants: te sach ky nang x hoi. hieu he nam thuc dan dan ((ca tu) or (ca tru)) tieng*.