Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
van tai » von tai, van tuan
y nang » ky nang, ly nang, v nang
luc va » duc va, tuc va
loc va » hoc va
tai va » thai va, mai va, tri va
thiet » thieu

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 (thuat sach)) y nang ma hoa. hieu van cham ((luc va) or (loc va)) van tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuat sach)) y nang ma hoa. hieu van cham ((luc va) OR (loc va)) van tai va thiet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuat sach)) y nang ma hoa. hieu van cham ((luc va) or (loc va)) van tai va thiet*.