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
luan san » luan van, luan hoan, luan phan
te sach » toc sach
doi tac » dong tac
cuu mot » cua mot, cuu mo, huu mot
ma khoa » may khoa, mai khoa, da khoa
san van » tan van, luan van, tran van

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 khoa luan san 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 khoa luan san van.
• Adding a wildcard symbol may retrieve word variants: te sach doi tac, nghien cuu mot ((hoc danh) or (hoc hanh)) khoa hoc ma khoa luan san van*.