Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
dua tren » dung tren
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van lam » van nam
loc va » hoc va, luc va
cua te » cua tu

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 ky nang xa hoi. hieu van lam ((loc va) or (duc va)) hanh vi ((dua tren) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu van lam ((loc va) OR (duc va)) hanh vi ((dua tren) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu van lam ((loc va) or (duc va)) hanh vi ((dua tren) or (cua te))*.