Perhaps you should try some spelling variations:
nganh dang » ngan hang, nhan dang, nganh cong
dang thuoc » dung thuoc
sach hoi » sach doi, sach moi, cach thoi
dong hoc » dong co, dong luc
thuoc xa » thuoc ma, thuoc va, thuoc la
gian dan » gian lang
tu sach » thu sach, su sach, te sach
hoi tai » hoc tai, hoi trac
mon hoc » toan hoc
va gian » va gianh, van gian, va giai

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 hoi tai, nghien cuu ((mon hoc) or (dong hoc)) nganh dang thuoc xa hoi va gian dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoi tai, nghien cuu ((mon hoc) OR (dong hoc)) nganh dang thuoc xa hoi va gian dan.
• Adding a wildcard symbol may retrieve word variants: tu sach hoi tai, nghien cuu ((mon hoc) or (dong hoc)) nganh dang thuoc xa hoi va gian dan*.