Perhaps you should try some spelling variations:
thien van » thi van
thu sach » tu sach, thuat sach, thuoc sach
toc sach » hoc sach, doc sach, thuoc sach
nam thuc » nam thuoc, am thuc, nam thu
hanh tai » thanh tai, hang tai, han tai
ky dang » ky danh
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet

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) or (toc sach)) ((ky dang) OR (ky nang)) xa hoi. thien van nam thuc va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (toc sach)) ((ky dang) OR (ky nang)) xa hoi. thien van nam thuc va hanh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (toc sach)) ((ky dang) OR (ky nang)) xa hoi. thien van nam thuc va hanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (toc sach)) ((ky dang) OR (ky nang)) xa hoi. thien van nam thuc va hanh tai cua tre*.