Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
duc manh » suc manh, duc anh, duc minh
phan lap » phan dau
nam viet » pham viet, lam viec, bac viet
ty nang » ty xang, ty hang, ly nang
duc van » duc va, duc tan, duc phan
lap nam » dap nam, lai nam, loai nam
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: thu sach ((ty nang) or (ky nang)) x hoi. hieu van cham ((duc van) OR (duc manh)) phan lap nam viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty nang) OR (ky nang)) x hoi. hieu van cham ((duc van) OR (duc manh)) phan lap nam viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ty nang) or (ky nang)) x hoi. hieu van cham ((duc van) OR (duc manh)) phan lap nam viet".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ty nang) or (ky nang)) x hoi. hieu van cham ((duc van) OR (duc manh)) phan lap nam viet*.