Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
sach doi » sach hoi, sach moi, sach dao
cong hoc » dong hoc, cong hoa, cong coc
hoc phan » hoc dan, hoc pho
phan hoa » phan loai, phan phoi, phan hong
mai khoi » mai khoa, tai khoa, cac khoi
nhan dan » phan dau, gian dan, nhan tai
tu sach » thu sach, su sach, te sach
doi tai » hoi tai, dai tai, doi tac
mai hoi » dai hoi, lai hoi, mai doi

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 thu cong hoc phan hoa hoc ((mai hoi) or (mai khoi)) ca nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach doi tai, nghien thu cong hoc phan hoa hoc ((mai hoi) OR (mai khoi)) ca nhan dan.
• Adding a wildcard symbol may retrieve word variants: tu sach doi tai, nghien thu cong hoc phan hoa hoc ((mai hoi) or (mai khoi)) ca nhan dan*.