Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
sach thuc » cach thuc, sach thu, sach thue
toc sach » hoc sach, doc sach, thuoc sach
thuc tap » tuc tap, thuc thai, thuc vat
cong hoc » dong hoc, cong hoa, cong coc
hoc hang » hoc hanh, hoc bang, hoc tang
hang hoa » hang khoa, thanh hoa, hang va
van nhan » van phan, van thanh, danh nhan
va phan » van phan, va phat, va phap
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach thuc tap, nghien thu cong hoc hang hoa hoc ma hoi ((va phan) or (van nhan)) van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thuc tap, nghien thu cong hoc hang hoa hoc ma hoi ((va phan) OR (van nhan)) van.
• Adding a wildcard symbol may retrieve word variants: toc sach thuc tap, nghien thu cong hoc hang hoa hoc ma hoi ((va phan) or (van nhan)) van*.