Perhaps you should try some spelling variations:
loai thanh » oai thanh, lai thanh, hoai thanh
thanh dong » thanh duong, thanh cong, hanh dong
mot loai » moi loai, mot ngoai, so loai
dong hoc » dong co, dong luc
van tinh » van thinh, van minh, ban tinh
tu sach » thu sach, su sach, te sach
hoi tap » hoi dap, hoc tap, hoi tai
hoc tai » hoc dai, hoc tap, hoc bai
cuu mot » cua mot, cuu mo, huu mot
hai van » thai van, ha van, hai tan
ma hai » ta hai, va hai, xa hai
toan » tran

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 ((hoi tap) or (hoc tai)), nghien cuu mot loai thanh dong hoc ma hai van tinh toan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((hoi tap) OR (hoc tai)), nghien cuu mot loai thanh dong hoc ma hai van tinh toan.
• Adding a wildcard symbol may retrieve word variants: tu sach ((hoi tap) or (hoc tai)), nghien cuu mot loai thanh dong hoc ma hai van tinh toan*.