Perhaps you should try some spelling variations:
vat hanh » vat thanh, van hanh, va hanh
cao thuc » cao thuoc, bao thuc, can thuc
tu sach » thu sach, su sach, tu cach
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
te sach » toc sach
va cau » van cau, va cac, va dau
va chu » va che, va chi
ve cao » va cao, ve bao, ve cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (te sach)) ty nang xa hoi. hieu ve cao thuc vat hanh ((va cau) or (va chu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ty nang xa hoi. hieu ve cao thuc vat hanh ((va cau) OR (va chu)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ty nang xa hoi. hieu ve cao thuc vat hanh ((va cau) or (va chu)) tre*.