Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
hanh tai » thanh tai, hang tai, han tai
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
tai cua » thai cua, tai cuc, tri cua
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
luc va » tuc va, loc 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 v nang xa hoi. ((hieu van) or (hieu va)) thanh ((luc va) OR (duc va)) hanh tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach v nang xa hoi. ((hieu van) OR (hieu va)) thanh ((luc va) OR (duc va)) hanh tai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach v nang xa hoi. ((hieu van) or (hieu va)) thanh ((luc va) OR (duc va)) hanh tai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach v nang xa hoi. ((hieu van) or (hieu va)) thanh ((luc va) OR (duc va)) hanh tai cua te*.