Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va pham » van pham, va phat, va phap
de cua » le cua, dieu cua
te cua » tue cua, le cua

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

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