Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
dang xay » dang van, van xay
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, va danh
sach ty » sach y, sach tu, sach thu
ve nham » ve nha, ve cham
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
va anh » van anh, va danh, va banh
le cua » ly cua
cua te » cua tu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (dang xay)) hoi. hieu ve nham thuc ((va anh) OR (va hanh)) le cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((nang xa) or (dang xay)) hoi. hieu ve nham thuc ((va anh) OR (va hanh)) le cua te~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang xa) or (dang xay)) hoi. hieu ve nham thuc ((va anh) OR (va hanh)) le cua te*.