Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
tinh vi » trinh vi, tinh voi, tinh va
va tinh » may tinh
cac toc » cac toi, cac nuoc, cac thoi
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
tu sach » thu sach, su sach, te sach
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
cac loc » cac lop, cac hoc, cac nuoc
vi cua » vai cua, di cua

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 ty ((nang xa) OR (lang xa)) hoi. hieu va ((cac loc) or (cac toc)) va tinh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (lang xa)) hoi. hieu va ((cac loc) OR (cac toc)) va tinh vi cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((nang xa) OR (lang xa)) hoi. hieu va ((cac loc) or (cac toc)) va tinh vi cua triet*".