Perhaps you should try some spelling variations:
dua tren » dung tren
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cac xuc » cac nuoc, chat xuc, cac cuoc
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo

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 ky nang xa hoi. hieu ve ((cac xuc) OR (cam xuc)) va hanh vi ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu ve ((cac xuc) OR (cam xuc)) va hanh vi ((dua tren) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu ve ((cac xuc) OR (cam xuc)) va hanh vi ((dua tren) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu ve ((cac xuc) OR (cam xuc)) va hanh vi ((dua tren) or (cuu tre))*.