Perhaps you should try some spelling variations:
su sach » vu sach
ky tang » ky nang, ky dang, kho tang
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
lap lai » lap tai, lay lai, lam lai
ky sang » ky nang, ky dang, duy sang
so sach » so sanh, bo sach, co sach
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan 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: ((su sach) OR (so sach)) ((ky sang) or (ky tang)) lap lai. hieu ve cac luc va dan vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ((ky sang) OR (ky tang)) lap lai. hieu ve cac luc va dan vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (so sach)) ((ky sang) or (ky tang)) lap lai. hieu ve cac luc va dan vi cua te".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (so sach)) ((ky sang) or (ky tang)) lap lai. hieu ve cac luc va dan vi cua te*.