Perhaps you should try some spelling variations:
lap hoat » tap hoa, dan hoat, lap dat
duy sang » duy van, duy can, duy anh
doan vi » doan va, don vi, doan thi
va doan » va doanh, van doan, va dan
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
so sach » so sanh, bo sach, co sach
ky tang » ky nang, ky dang, kho tang
ky sang » ky nang, ky dang
ve cac » va cac, vien cac
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: so sach ((((ky sang) or (duy sang))) or (ky tang)) lap hoat. hieu ve cac luc va doan vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((((ky sang) OR (duy sang))) OR (ky tang)) lap hoat. hieu ve cac luc va doan vi cua te.
• Adding a wildcard symbol may retrieve word variants: so sach ((((ky sang) or (duy sang))) or (ky tang)) lap hoat. hieu ve cac luc va doan vi cua te*.