Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach ty, sach kem
hanh di » hanh vi, hanh de, hang di
qua van » quan van, qua ban, qua san
nam qua » nam quan, nam cua, nam mua
hieu ca » hieu cac, hieu cua, hieu va
cua tre » cua te, cuu tre, cua triet
hieu ha » hieu hoa, hieu va, hieu xa
di cua » dai cua, doi 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: tu ((sach ky) or (sach y)) nang x hoi. ((hieu ha) or (hieu ca)) nam qua van hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) nang x hoi. ((hieu ha) OR (hieu ca)) nam qua van hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach y)) nang x hoi. ((hieu ha) or (hieu ca)) nam qua van hanh di cua tre*.