Perhaps you should try some spelling variations:
doanh van » doan van, doanh va, doanh ban
sach thue » sach thieu, sach tham, cach thuc
sach thu » sach thieu, sach tham, cach thuc
van cua » vang cua, ban cua, dan cua
hieu vu » hieu va, hieu ve, hieu su
vu kham » vu khanh
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach thu) or (sach thue)) nang xa hoi. hieu vu kham ((tuc va) or (duc va)) doanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thu) OR (sach thue)) nang xa hoi. hieu vu kham ((tuc va) OR (duc va)) doanh van cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach thu) or (sach thue)) nang xa hoi. hieu vu kham ((tuc va) or (duc va)) doanh van cua tre*.