Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
van hanh » van thanh, ban hanh, van anh
dua tren » dung tren
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
dau tuc » dau tu, dao tuc, cau truc
tuc van » thuc van, truc van, tuc va
va dau » va dao

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty nang xa hoi. lieu va dau tuc van hanh vi ((dua tren) or (((cua triet) OR (va triet))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang xa hoi. lieu va dau tuc van hanh vi ((dua tren) OR (((cua triet) OR (va triet))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang xa hoi. lieu va dau tuc van hanh vi ((dua tren) or (((cua triet) OR (va triet))))*".