Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
van doanh » toan doanh, van dong, van thanh
doanh va » doan va, doanh tai, doanh cua
sach kem » hanh kem
cach le » cach de, cach ben, cach lam
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, nang ma
cac le » cac he, mac le, bac le
sac ky » cac ky, sai ky
va cua » va chua, via cua, ca cua

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 kem) or (sac ky)) nang xa hoi. hieu hien ((cac le) OR (cach le)) van doanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach kem) OR (sac ky)) nang xa hoi. hieu hien ((cac le) OR (cach le)) van doanh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach kem) or (sac ky)) nang xa hoi. hieu hien ((cac le) OR (cach le)) van doanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach kem) or (sac ky)) nang xa hoi. hieu hien ((cac le) OR (cach le)) van doanh va cua tre*.