Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
nhanh dong » hanh dong, nhanh chong, anh dong
hoc nhanh » hoc nganh, hoc phan
sach doi » sach hoi, sach moi, sach dao
dong hoa » dong hoc, dong co
nhan tai » hang tai, van tai, toan tai
so sach » so sanh, bo sach, co sach
doi tap » doi tac, doi dap, doi tai
mot hoc » mon hoc, mo hoc, mot goc
mai hoi » mai khoi, dai hoi, lai hoi
va nhan » van nhan, ca nhan, va phan
ma hoi » xa hoi, ma hoa, me hoi

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 doi tap, nghien cua mot hoc nhanh dong hoa ((ma hoi) OR (mai hoi)) va nhan tai~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach doi tap, nghien cua mot hoc nhanh dong hoa ((ma hoi) OR (mai hoi)) va nhan tai*".