Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
nam truc » nam truoc, nam thuc, nam trung
va thanh » gia thanh, ban thanh, va tinh
thai cua » than cua, tai cuc, tri cua
ky lang » ky nang, ky tang, tay lang
ky dang » ky nang, ky danh
truc va » thuc va, thuc vat, trung va
hai cua » dai cua, hoi cua, lai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ky lang) or (ky dang)) xa hoi. thien van nam truc va thanh ((hai cua) OR (thai cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ky lang) OR (ky dang)) xa hoi. thien van nam truc va thanh ((hai cua) OR (thai cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((ky lang) or (ky dang)) xa hoi. thien van nam truc va thanh ((hai cua) OR (thai cua)) te".
• Adding a wildcard symbol may retrieve word variants: toc sach ((ky lang) or (ky dang)) xa hoi. thien van nam truc va thanh ((hai cua) OR (thai cua)) te*.