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
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
han tai » hang tai, nhan tai, van tai
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
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: thu sach ((ky lang) OR (ky tang)) xa hoi. hieu van cham ((xuc va) or (tuc va)) han tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ky lang) OR (ky tang)) xa hoi. hieu van cham ((xuc va) OR (tuc va)) han tai va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ky lang) OR (ky tang)) xa hoi. hieu van cham ((xuc va) or (tuc va)) han tai va thiet".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky lang) OR (ky tang)) xa hoi. hieu van cham ((xuc va) or (tuc va)) han tai va thiet*.