Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
danh doi » danh di, thanh doi, dung doi
trung va » truong va, trang va, trung ha
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van cac » van hac, van cau, van bac
truc va » thuc va, thuc vat
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, dua tren

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang xa hoi. hieu van cac ((truc va) or (trung va)) danh doi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. hieu van cac ((truc va) OR (trung va)) danh doi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang xa hoi. hieu van cac ((truc va) or (trung va)) danh doi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. hieu van cac ((truc va) or (trung va)) danh doi ((cua tre) OR (cua triet))*.