Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cac truc » cau truc, cac tru, cac trung
dua tren » dung tren
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
van cac » van hac, van cau, van bac
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cua triet, cua thep
cuu tre » cau tren, cau treo
y nang » ky nang, ly nang, v nang
phat » phan, pham, phap

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 y nang xa hoi. hieu van cac truc va phat vi ((((cua tre) OR (dua tren))) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang xa hoi. hieu van cac truc va phat vi ((((cua tre) OR (dua tren))) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang xa hoi. hieu van cac truc va phat vi ((((cua tre) OR (dua tren))) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: su sach y nang xa hoi. hieu van cac truc va phat vi ((((cua tre) OR (dua tren))) or (cuu tre))*.