Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
truc va » thuc va, trung va
van cau » van dau, van hau, van chat
te sach » toc sach
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
cua tre » cua te, cuu tre, cua triet
dan te » van te, dan tu, dan ve
te cua » tue cua, le cua, de cua
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ty nang) or (ty hang)) x hoi. hieu van cau ((truc va) OR (thuc vat)) dan te cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty nang) OR (ty hang)) x hoi. hieu van cau ((truc va) OR (thuc vat)) dan te cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty nang) or (ty hang)) x hoi. hieu van cau ((truc va) OR (thuc vat)) dan te cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ((ty nang) or (ty hang)) x hoi. hieu van cau ((truc va) OR (thuc vat)) dan te cua tre*.