Perhaps you should try some spelling variations:
cac truc » cau truc, cac tru, cac trung
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
ve cac » va cac, vien cac
vi cua » vai cua
di cua » doi cua, de cua, do cua

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