Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
van cam » van nam, van lam, van cau
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
tuc va » thuc va, tuc xa, duc va
luc va » duc va, loc va

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 ty nang xa hoi. hieu van cam ((((luc va) or (tuc va))) or (truc va)) hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang xa hoi. hieu van cam ((((luc va) OR (tuc va))) OR (truc va)) hanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty nang xa hoi. hieu van cam ((((luc va) or (tuc va))) or (truc va)) hanh dai cua tre*.