Perhaps you should try some spelling variations:
nghien huu » nghien cuu, nguyen huu, nhiem huu
nhan khong » nhan thong, nhanh chong, nganh khong
dung tren » dung trong, dung trung
tren nhan » trien nhan, tran nhan, tren phan
khong hoc » khung hoc, thong hoc, khong thuoc
gian lang » gian dan
sach doi » sach hoi, sach moi, sach dao
huu dung » huu tung, huu quang, thuy dung
nhan van » nhan dan, nhan va, phan van
tu sach » thu sach, su sach, te sach
doi tai » hoi tai, dai tai, doi tac
hoc xa » hoc ma

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 doi tai, nghien huu dung tren nhan khong hoc xa hoi va ((nhan van) or (gian lang))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach doi tai, nghien huu dung tren nhan khong hoc xa hoi va ((nhan van) OR (gian lang)).
• Adding a wildcard symbol may retrieve word variants: tu sach doi tai, nghien huu dung tren nhan khong hoc xa hoi va ((nhan van) or (gian lang))*.