Perhaps you should try some spelling variations:
nang hoang » dang hoang, nang hang, quang hoang
hoang xanh » hoang anh, hoang van, hoang minh
sach hoc » cach hoc, sach hoi, mach hoc
cuu nang » chuc nang, cam nang, cuu van
xanh hoa » xanh khoa, danh hoa, hanh hoa
nhan dan » phan dau, gian dan, nhan tai
toan tai » toan tap, doanh tai, toan ban
su sach » so sach, vu sach
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: su sach hoc tap, nghien cuu nang hoang xanh hoa hoc xa hoi va ((nhan dan) or (toan tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoc tap, nghien cuu nang hoang xanh hoa hoc xa hoi va ((nhan dan) OR (toan tai)).
• Adding a wildcard symbol may retrieve word variants: su sach hoc tap, nghien cuu nang hoang xanh hoa hoc xa hoi va ((nhan dan) or (toan tai))*.