Perhaps you should try some spelling variations:
hoc nganh » hoc nhanh
gianh dan » gian dan, giang day, giang van
sach hoc » cach hoc, sach hoi, mach hoc
cuu cong » cua cong, thu cong, cac cong
cong hoc » dong hoc, cong hoa, cong coc
va gianh » va gian, van giang, va giai
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach hoc tap, nghien cuu cong hoc nganh ((khoa hoc) OR (hoa hoc)) xa hoi va gianh dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach hoc tap, nghien cuu cong hoc nganh ((khoa hoc) OR (hoa hoc)) xa hoi va gianh dan".
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu cong hoc nganh ((khoa hoc) OR (hoa hoc)) xa hoi va gianh dan*.