Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
sach thoi » cach thoi, sach hoi, sach tham
thoi dai » hoc dai, hoi dap, hoi dan
dan khoa » dang khoa, da khoa, san khoa
khoa hoc » hoa hoc
nhan dan » phan dau, gian dan, nhan tai
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong hoc
hai tan » hai quan
hai van » thai van, ha van, hao van
hoc xa » hoc ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach thoi dai, nghien cuu mon hoc dan khoa hoc xa ((hai tan) OR (hai van)) nhan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach thoi dai, nghien cuu mon hoc dan khoa hoc xa ((hai tan) OR (hai van)) nhan dan".
• Adding a wildcard symbol may retrieve word variants: thuoc sach thoi dai, nghien cuu mon hoc dan khoa hoc xa ((hai tan) OR (hai van)) nhan dan*.