Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
danh hai » dang hai, lanh hai, manh hai
hai cua » thai cua, dai cua, hoi cua
va danh » va dinh, va dan, va hanh
cao duc » dao duc, giao duc, tao duoc
cao suc » cao su
nang xa » lang xa, nang ma, mang xa
sach tu » sach thu, cach tu, sach ty
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach tu ((nang xa) or (nang x)) hoi. hieu qua ((cao suc) OR (cao duc)) va danh hai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tu ((nang xa) OR (nang x)) hoi. hieu qua ((cao suc) OR (cao duc)) va danh hai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach tu ((nang xa) or (nang x)) hoi. hieu qua ((cao suc) OR (cao duc)) va danh hai cua te".
• Adding a wildcard symbol may retrieve word variants: toc sach tu ((nang xa) or (nang x)) hoi. hieu qua ((cao suc) OR (cao duc)) va danh hai cua te*.