Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
cua tre » cua te, cua triet, dua tren
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
cac duc » cac du, cao duc, cac dac
cuu tre » cau tren, cau treo
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
ve cac » va cac, vien cac

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