Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
duc manh » suc manh, duc anh, duc minh
hanh lai » hanh lam, hanh tai, thanh lap
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va, hieu van
duc van » duc va, duc tan, duc phan
lai cua » dai cua, hai cua, lai chau
ve cam » ve cham, ve cac, va cam
x hoi » xa hoi, o hoi, x ho

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 ky) OR (sach y)) nang x hoi. hieu ve cam ((duc van) or (duc manh)) hanh lai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach y)) nang x hoi. hieu ve cam ((duc van) OR (duc manh)) hanh lai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sach y)) nang x hoi. hieu ve cam ((duc van) or (duc manh)) hanh lai cua triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) OR (sach y)) nang x hoi. hieu ve cam ((duc van) or (duc manh)) hanh lai cua triet*.