Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ly quang » le quang, vu quang
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc dan, thuc day
van cam » van nam, van lam, van cau
ly vang » ly hang, ly van
cuu tre » cua tre, cau tren, cau treo
luc va » duc va, tuc va, loc va
vi cuu » vi luu, vinh cuu

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 ((ly vang) OR (ly quang)) xa hoi. hieu van cam ((luc va) or (thuc va)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ly vang) OR (ly quang)) xa hoi. hieu van cam ((luc va) OR (thuc va)) hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ly vang) OR (ly quang)) xa hoi. hieu van cam ((luc va) or (thuc va)) hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ly vang) OR (ly quang)) xa hoi. hieu van cam ((luc va) or (thuc va)) hanh vi cuu tre*.