Perhaps you should try some spelling variations:
hien cac » thien cac, hieu cac, dien cac
hanh dai » hanh tai, hanh dao, vanh dai
van hanh » van thanh, ban hanh, van anh
nuoc van » nuoc va, nuoc san, luoc van
vien cac » vien bach, vien dai, vien da
sach ly » sach y, sach ty, sach hay
nang xa » nang x, lang xa, nang ma
sach lo » sach dao, sach doi, sach hoi
cua tu » cua tuc, cua su, cua cu

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 ly) or (sach lo)) nang xa hoi. hieu ((hien cac) OR (vien cac)) nuoc van hanh dai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ly) OR (sach lo)) nang xa hoi. hieu ((hien cac) OR (vien cac)) nuoc van hanh dai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ly) or (sach lo)) nang xa hoi. hieu ((hien cac) OR (vien cac)) nuoc van hanh dai cua tu".
• Adding a wildcard symbol may retrieve word variants: te ((sach ly) or (sach lo)) nang xa hoi. hieu ((hien cac) OR (vien cac)) nuoc van hanh dai cua tu*.