Perhaps you should try some spelling variations:
van hoang » quan hoang, tran hoang, tuan hoang
va triet » va thiet, va trien, ve triet
nam thuc » nam thuoc, am thuc, nam thu
thi nang » thi cong, ki nang, thi hanh
van hoan » van hoa, van toan, van han
sach thi » sach thu, sach tai, sach thieu
su sach » so sach, vu sach
cam tuc » cam xuc, cam tu, dam thuc
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
di va » dai va, di vao, doi va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thi nang xa hoi. hieu va ((cam tuc) OR (nam thuc)) ((van hoang) OR (van hoan)) di va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thi nang xa hoi. hieu va ((cam tuc) OR (nam thuc)) ((van hoang) or (van hoan)) di va triet~".
• Adding a wildcard symbol may retrieve word variants: su sach thi nang xa hoi. hieu va ((cam tuc) OR (nam thuc)) ((van hoang) or (van hoan)) di va triet*.