Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
hieu van » hieu va, thien van, lieu va
ban hang » ngan hang
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
hoi cua » hoi chuc
y nang » ky nang, ly nang, v nang
van am » van nam, van lam, van dam
am hoc » ad hoc
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 y nang xa hoi. hieu van am hoc ((dan thanh) or (ban hang)) hoi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y nang xa hoi. hieu van am hoc ((dan thanh) OR (ban hang)) hoi cua tu.
• Adding a wildcard symbol may retrieve word variants: so sach y nang xa hoi. hieu van am hoc ((dan thanh) or (ban hang)) hoi cua tu*.