Perhaps you should try some spelling variations:
nganh dong » nganh cong, nhanh dong, nganh nong
dong thuoc » dung thuoc, dang thuoc, don thuoc
sach hoc » cach hoc, sach hoi, mach hoc
dong hoc » dong co
dong luc » nang luc
thuoc va » thuc va, thuoc ma, thuong va
nhan tai » hang tai, van tai, toan tai
tu sach » thu sach, su sach, te sach
va nhan » van nhan, ca nhan, va phan
va hoi » xa hoi, va hoc, va hoa

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