Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
luc van » luoc van, luu van, duc van
cua tre » cuu tre, cua triet, dua tren
hanh le » thanh le, hanh ve, hanh de
nang xa » nang x, lang xa, nang ma
van ha » van hoa, van chat, van phan
ha luc » ha duc, nhan luc, than luc
v nang » va nang, vu nang, van nang
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: ((te sach) or (toc sach)) v nang xa hoi. hieu van ha luc van hanh le ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) v nang xa hoi. hieu van ha luc van hanh le ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) v nang xa hoi. hieu van ha luc van hanh le ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) v nang xa hoi. hieu van ha luc van hanh le ((cua tre) OR (cua te))*.