Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, lieu va
van chat » cao chat
ky lang » ky nang, ky tang, tay lang
ky dang » ky nang, ky danh
cuc tre » duc tre, cua tre, cuu tre
luc va » duc va, tuc va
loc va » hoc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ((ky lang) or (ky dang)) xa hoi. hieu van chat ((luc va) OR (loc va)) doanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((ky lang) OR (ky dang)) xa hoi. hieu van chat ((luc va) OR (loc va)) doanh tai cuc tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ((ky lang) or (ky dang)) xa hoi. hieu van chat ((luc va) OR (loc va)) doanh tai cuc tre*".