Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghe cua
nghiep vua » nghiep va, nghiep vu
doanh khoa » toan khoa
hoc doanh » hoa doanh, hoc danh, hoc dan
van thanh » ban thanh, van tuan
sach hoi » sach doi, sach moi, cach thoi
cong hoc » dong hoc, cong hoa, cong coc
khoa hoc » hoa hoc
su sach » so sach, vu sach
hoi tai » hoc tai, hoi trac
hai van » thai van, ha van, hai tan
ma hai » ta hai, va hai, xa hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach hoi tai, ((nghien cua) or (nghiep vua)) cong hoc doanh khoa hoc ma hai van thanh san~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoi tai, ((nghien cua) OR (nghiep vua)) cong hoc doanh khoa hoc ma hai van thanh san.
• Adding a wildcard symbol may retrieve word variants: su sach hoi tai, ((nghien cua) or (nghiep vua)) cong hoc doanh khoa hoc ma hai van thanh san*.