Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
lang xa » dang xay, lang van
lang ha » long ha
qua cac » cua cac
cac luc » cau luc, coc luc, cac nuoc
va hanh » van hanh, va thanh, va danh
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua
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 y ((lang xa) or (lang ha)) hoi. hieu qua cac luc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y ((lang xa) OR (lang ha)) hoi. hieu qua cac luc va hanh vi cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach y ((lang xa) or (lang ha)) hoi. hieu qua cac luc va hanh vi cua te*.