Perhaps you should try some spelling variations:
nguoi sach » nguoi san, nuoc sach
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
thanh va » thanh van, hanh va, thanh ha
bo sach » co sach, hoc sach
nam duc » nam duoc, nam thuc, nam buoc
chu tre » cho tre, chu tri, cuu tre
va chu » va che, va cau, va chi
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((bo sach) or (nguoi sach)) ky nang x hoi. hieu van ((nam duc) or (pham duc)) va thanh va chu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((bo sach) OR (nguoi sach)) ky nang x hoi. hieu van ((nam duc) OR (pham duc)) va thanh va chu tre.
• Adding a wildcard symbol may retrieve word variants: ((bo sach) or (nguoi sach)) ky nang x hoi. hieu van ((nam duc) or (pham duc)) va thanh va chu tre*.