Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cao luc » bao luc, cao duc, cao suc
luc van » luoc van, luu van, duc van
hanh ki » hanh ky, hanh kien, thanh kim
su tren » su tien, tu tren, cu tren
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
va cao » va cac, va co, va dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((y nang) or (v nang)) xa hoi. lieu va cao luc van ((hanh ki) or (hanh vi)) su tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y nang) OR (v nang)) xa hoi. lieu va cao luc van ((hanh ki) OR (hanh vi)) su tren.
• Adding a wildcard symbol may retrieve word variants: thu sach ((y nang) or (v nang)) xa hoi. lieu va cao luc van ((hanh ki) or (hanh vi)) su tren*.