Perhaps you should try some spelling variations:
sach doanh » sach danh, sach tranh, cac doanh
nghiep vua » nghiep va, nghiep vu
sanh trong » sinh trong, anh trong, hanh trong
sach tron » sach tren, sach tranh, sach tien
nghien d » nghiem d, nghien o, nghiem de
so sach » so sanh, bo sach, co sach
vua hoc » va hoc, cua hoc, luan hoc
d hoc » du hoc, ad hoc, de hoc

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 doanh nghiep vua hoc ) or ( su ((sach tron) or (sanh trong)) nghien d hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sach doanh nghiep vua hoc ) OR ( su ((sach tron) OR (sanh trong)) nghien d hoc )).
• Adding a wildcard symbol may retrieve word variants: (( so sach doanh nghiep vua hoc ) or ( su ((sach tron) or (sanh trong)) nghien d hoc ))*.