Perhaps you should try some spelling variations:
hanh noi » ha noi, hanh vi, nang noi
sach hoi » sach doi, sach moi, cach thoi
van hanh » van thanh, ban hanh, van anh
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
cua vuc » cua duc, cua tuc, cua vu
vuc van » duc van, luc van, thuc van
cua tu » cua tuc, cua cu, cua te
va cua » va chua, via cua, ca cua
cua su » qua su

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