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
te sach » toc sach
doi tac » dong tac
cuu mon » cuu mo, cuu mot, cuu cong
ma khoa » may khoa, mai khoa, da khoa
luan » quan, lan

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 mon ((hoc danh) OR (hoc hanh)) khoa hoc ma khoa luan van ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach doi tac, nghien cuu mon ((hoc danh) OR (hoc hanh)) khoa hoc ma khoa luan van ban".
• Adding a wildcard symbol may retrieve word variants: te sach doi tac, nghien cuu mon ((hoc danh) OR (hoc hanh)) khoa hoc ma khoa luan van ban*.