Perhaps you should try some spelling variations:
cham duc » pham duc, cham soc, pham duy
su sach » so sach, vu sach
va chua » vua chua, ca chua, a chua
va tinh » may tinh
sach tu » sach thu, cach tu, sach ty
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
va chu » va che, va cau, va chi

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 tu ((nang xa) or (lang xa)) hoi. hieu vu cham duc va tinh ((va chua) OR (va chu)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu ((nang xa) OR (lang xa)) hoi. hieu vu cham duc va tinh ((va chua) OR (va chu)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach tu ((nang xa) or (lang xa)) hoi. hieu vu cham duc va tinh ((va chua) OR (va chu)) te".
• Adding a wildcard symbol may retrieve word variants: su sach tu ((nang xa) or (lang xa)) hoi. hieu vu cham duc va tinh ((va chua) OR (va chu)) te*.