Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
dan thanh » dang thanh, danh thanh, van thanh
hieu van » hieu va, thien van, lieu va
cam thuc » am thuc, nam thuc, cam thu
so sach » so sanh, bo sach, co sach
doi cua » dai cua, hoi cua
van cam » van nam, van lam, van cau
vu nang » vuc nang, va nang, vu dang
y nang » ky nang, ly nang, v 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: so sach ((y nang) or (vu nang)) xa hoi. hieu van cam thuc ((dan thanh) or (ban thanh)) doi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((y nang) OR (vu nang)) xa hoi. hieu van cam thuc ((dan thanh) OR (ban thanh)) doi cua tu.
• Adding a wildcard symbol may retrieve word variants: so sach ((y nang) or (vu nang)) xa hoi. hieu van cam thuc ((dan thanh) or (ban thanh)) doi cua tu*.