Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
nang dau » hang dau, xang dau, nang du
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
cam tuc » cam tu, nam thuc, dam thuc
sach ty » sach tu, sach thu, xach tay
dau hoi » cau hoi, dai hoi, dan hoi
va cua » va chua, via cua, ca 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 ty) or (sach y)) nang dau hoi. hieu qua ((cam tuc) OR (cam xuc)) va hanh va cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach y)) nang dau hoi. hieu qua ((cam tuc) OR (cam xuc)) va hanh va cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) or (sach y)) nang dau hoi. hieu qua ((cam tuc) OR (cam xuc)) va hanh va cua triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach y)) nang dau hoi. hieu qua ((cam tuc) OR (cam xuc)) va hanh va cua triet*.