Perhaps you should try some spelling variations:
cau triet » cau trieu, su triet, cua triet
tay quang » tac quang, tai quang, tao quang
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
cac thu » cach thuc, cac thoi
va hanh » van hanh, va thanh, va danh
cac tu » cach tu, cac du, tac tu
vi cau » va cau, ve cau, di cau

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