Perhaps you should try some spelling variations:
tu thiet » tu thien, tu triet, thua thiet
sach ky » sach y, sach ty, sach kem
hanh de » hanh ve, hanh kem
va hanh » van hanh, va thanh, va danh
cao duc » dao duc, cao suc, giao duc
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
va cao » va cac, va co, va dao
sac ky » cac ky, sai ky
de tu » do tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sac ky)) ((nang xa) or (lang xa)) hoi. hieu va cao duc va hanh de tu thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) ((nang xa) OR (lang xa)) hoi. hieu va cao duc va hanh de tu thiet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) ((nang xa) or (lang xa)) hoi. hieu va cao duc va hanh de tu thiet*.