Perhaps you should try some spelling variations:
sach doi » sach hoi, sach moi, sach dao
hoc danh » hoc dan, hoc anh, hoc nganh
hoc hanh » hoc nhanh, hoc thanh, hoc anh
khoa hoc » hoa hoc
hoc luan » hoc quan, nuoc luan, hoc luong
te sach » toc sach
doi tac » dong tac
cuu mot » cua mot, cuu mo, huu mot
van van » van ban, tan van, san van
ma hoc » va hoc, ma hoa, mo hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach doi tac, nghien cuu mot ((hoc danh) or (hoc hanh)) khoa hoc ma hoc luan van van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach doi tac, nghien cuu mot ((hoc danh) OR (hoc hanh)) khoa hoc ma hoc luan van van.
• Adding a wildcard symbol may retrieve word variants: te sach doi tac, nghien cuu mot ((hoc danh) or (hoc hanh)) khoa hoc ma hoc luan van van*.