Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
hieu ve » hieu van
sach ky » sac ky, sach y, sach kem
hieu va » lieu va, hieu qua
cam loc » cam lo
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
loc va » hoc va, luc va
di cua » dai cua, doi cua, de cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) or (sach ty)) nang xa hoi. ((hieu ve) OR (hieu va)) cam loc va hanh di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sach ty)) nang xa hoi. ((hieu ve) OR (hieu va)) cam loc va hanh di cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sach ty)) nang xa hoi. ((hieu ve) OR (hieu va)) cam loc va hanh di cua viet".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sach ty)) nang xa hoi. ((hieu ve) OR (hieu va)) cam loc va hanh di cua viet*.