Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van chat » cao chat
danh dai » danh dau, danh di, danh sai
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
truc va » thuc vat, trung va
nang xa » nang x, lang xa, nang ma
y nang » ky nang, ly nang, v nang

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 y nang xa hoi. hieu van chat ((truc va) OR (thuc va)) danh dai ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang xa hoi. hieu van chat ((truc va) OR (thuc va)) danh dai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang xa hoi. hieu van chat ((truc va) OR (thuc va)) danh dai ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang xa hoi. hieu van chat ((truc va) OR (thuc va)) danh dai ((cua tre) or (cuu tre))*.