Perhaps you should try some spelling variations:
sach hoc » sach hoi, mach hoc, sach duoc
cach hoc » cach thuc, cach thoi, dich hoc
cuu dong » cuu cong, cuu tong, cuu long
dong luc » nang luc
chu nhan » chau nhan, cu nhan, chu han
nhan dan » phan dau, gian dan, nhan tai
luc anh » luc canh, duc anh, luu anh
anh hoa » anh khoa, danh hoa, hanh hoa
hoi chu » hoi chuc
hoc xa » hoc ma

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