Perhaps you should try some spelling variations:
khong hoc » thong hoc, khong thuoc, khong chuc
khung hoc » chung hoc, nhung hoc, thuong hoc
sach hoc » cach hoc, sach hoi, mach hoc
cuu dong » cuu cong, cuu tong, cuu long
dong luc » nang luc
van nhan » van phan, van thanh, danh nhan
nhan van » nhan dan, nhan va, phan van
tu sach » thu sach, su sach, te sach
hoi van » hoi va, hoi dan, hai van

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