Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
dua tren » dung tren
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
dau vuc » dau nuoc
vuc van » duc van, luc van, thuc van
y nang » ky nang, ly nang, v nang
va dau » va dao
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: tu sach y nang xa hoi. lieu va dau vuc van hanh vi ((dua tren) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. lieu va dau vuc van hanh vi ((dua tren) OR (cua tu)).
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. lieu va dau vuc van hanh vi ((dua tren) or (cua tu))*.