Perhaps you should try some spelling variations:
dung sai » dung tai, dung va, dung dat
va triet » va thiet, va trien, ve triet
van dung » van dong, xay dung, tin dung
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
sach ky » sach y, sach ty, sach kem
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
va cam » va cham, va cac, va cao
sac ky » cac ky, sai ky
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam duc van dung sai ((va triet) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam duc van dung sai ((va triet) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam duc van dung sai ((va triet) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam duc van dung sai ((va triet) or (cua tu))*.