Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cac trung » cac truong, dac trung, bac trung
van nang » van quang, van ban, van dong
trung va » truong va, trang va, trung ha
hieu va » lieu va, hieu qua
hanh di » hanh vi, hang di, danh di
hanh de » hanh ve, hanh kem
su sach » so sach, vu sach
v nang » va nang, vu nang, voi nang

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