Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
luoc van » luoc can, luoc va, luc van
cac luoc » cac nuoc, cac cuoc, cac quoc
hanh de » hanh ve, hanh kem
vu nang » vuc nang, va nang, vu dang
hieu ve » hieu va, hieu van
ve cac » va cac, vien cac
v nang » va nang, van nang, voi nang
cua tu » cua tuc, cua su, cua cu

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 ((v nang) or (vu nang)) xa hoi. hieu ve cac luoc van ((hanh de) or (hanh vi)) cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((v nang) OR (vu nang)) xa hoi. hieu ve cac luoc van ((hanh de) OR (hanh vi)) cua tu.
• Adding a wildcard symbol may retrieve word variants: toc sach ((v nang) or (vu nang)) xa hoi. hieu ve cac luoc van ((hanh de) or (hanh vi)) cua tu*.