Perhaps you should try some spelling variations:
vien dai » hien dai
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
te sach » toc sach
doi cua » dai cua, hoi cua
vien da » hien dai
sach lo » sach dao, sach doi, sach hoi
nang xa » nang x, lang xa, nang ma
lo nang » ho nang, ly nang, loai nang
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 lo nang xa hoi. hieu ((vien dai) or (vien da)) nuoc ((van hanh) OR (ban hanh)) doi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach lo nang xa hoi. hieu ((vien dai) OR (vien da)) nuoc ((van hanh) OR (ban hanh)) doi cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach lo nang xa hoi. hieu ((vien dai) or (vien da)) nuoc ((van hanh) OR (ban hanh)) doi cua tu".
• Adding a wildcard symbol may retrieve word variants: te sach lo nang xa hoi. hieu ((vien dai) or (vien da)) nuoc ((van hanh) OR (ban hanh)) doi cua tu*.