Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nghien huu » nghien cuu, nguyen huu, nhiem huu
sach hoc » cach hoc, sach hoi, mach hoc
dan khoa » dang khoa, san khoa, van khoa
von luan » tong luan
hai von » hai van, hai con, hai son
huu ho » huu co
ho hoc » hoa hoc, cho hoc, hoi hoc
hoc xa » hoc ma
xa hai » xa thai, xua hai, xa hoi

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 hoc tap, nghien huu ho hoc ((dan khoa) or (da khoa)) hoc xa hai von luan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach hoc tap, nghien huu ho hoc ((dan khoa) OR (da khoa)) hoc xa hai von luan van.
• Adding a wildcard symbol may retrieve word variants: thuoc sach hoc tap, nghien huu ho hoc ((dan khoa) or (da khoa)) hoc xa hai von luan van*.