Perhaps you should try some spelling variations:
dang thanh » dong thanh, dang hanh, hoang thanh
thuc dang » thuoc dang, thuc dan, thuc dung
thanh doi » thanh loi, thanh moi, thanh do
hieu van » hieu va, thien van, lieu va
cam thuc » am thuc, nam thuc, cam thu
so sach » bo sach, co sach, hoc sach
so sanh » do sanh
ly nang » ky nang, ly hang, ly vang
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
doi cua » dai cua, hoi cua
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (so sanh)) ly nang xa hoi. hieu van cam thuc dang thanh doi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) ly nang xa hoi. hieu van cam thuc dang thanh doi cua tu.
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (so sanh)) ly nang xa hoi. hieu van cam thuc dang thanh doi cua tu*.