Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
cac thuat » va thuat, hoc thuat, cac thu
thuat vat » thuat va, thuc vat, thuat xay
cong coc » cong cuoc, cong cac, cong co
coc hang » hoc hang, oc hang, moc hoang
hang hoa » hang khoa, thanh hoa, hang va
nhan tai » hang tai, van tai, toan tai
toc cac » hoc cac, tuc cac, ton cac
nhan va » nhan dan, nhan tao, phan van
hoc xa » hoc ma
hoi ca » hoi cua, hoi cac, hoi cau

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

• If you are trying to use Boolean operators, they must be ALL CAPS: toc cac thuat vat, nghien thu cong coc hang hoa hoc xa hoi ca ((nhan va) OR (nhan tai))~.
• Adding a wildcard symbol may retrieve word variants: toc cac thuat vat, nghien thu cong coc hang hoa hoc xa hoi ca ((nhan va) or (nhan tai))*.