Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
su triet » su tien, ve triet
dang xay » dang van, van xay
va thanh » gia thanh, ban thanh, va tinh
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
cac tuc » cac toc, cac tu, cac tac
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
su viet » so viet
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((nang xa) or (dang xay)) hoi. hieu va cac tuc va thanh doi ((su triet) OR (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (dang xay)) hoi. hieu va cac tuc va thanh doi ((su triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang xa) or (dang xay)) hoi. hieu va cac tuc va thanh doi ((su triet) OR (su viet))".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) or (dang xay)) hoi. hieu va cac tuc va thanh doi ((su triet) OR (su viet))*.