Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
te sach » toc sach
hanh va » hang va, hanh vi
thuc va » thuc vat, thuc day
hieu va » lieu va, hieu qua
tu nang » tru nang, tu nong, tu nano
cuu tre » cua tre, cau tren, cau treo
va cuu » va cau, va chu, va huu
va co » vo co

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((tu nang) or (truc nano)) xa hoi. hieu va co ((thuc va) OR (thuc dan)) hanh va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nang) OR (truc nano)) xa hoi. hieu va co ((thuc va) OR (thuc dan)) hanh va cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((tu nang) or (truc nano)) xa hoi. hieu va co ((thuc va) OR (thuc dan)) hanh va cuu tre".
• Adding a wildcard symbol may retrieve word variants: te sach ((tu nang) or (truc nano)) xa hoi. hieu va co ((thuc va) OR (thuc dan)) hanh va cuu tre*.