Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, dua tren
ve bac » ve bao, ve cac, ve ban
x hoi » xa hoi, o hoi, x ho
bo va » bao va, do va, so va

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 nang x hoi. hieu ve bac bo va hanh vi ((cua tre) OR (cua triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. hieu ve bac bo va hanh vi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu ve bac bo va hanh vi ((cua tre) OR (cua triet))*.