Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
sach ky » sach y, sach ty, sach kem
hieu va » lieu va, hieu qua
cao suc » cao su, cao duc
nang xa » nang x, lang xa, nang ma
va cao » va cac, va co, va dao
sac ky » cac ky, sai ky
suc va » duc va, tuc va, luc va
de su » den su, ve su, da su
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 hoi. hieu va cao suc va hanh ((de su) or (de tu)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang xa hoi. hieu va cao suc va hanh ((de su) OR (de tu)) triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang xa hoi. hieu va cao suc va hanh ((de su) or (de tu)) triet*.