Perhaps you should try some spelling variations:
dua tren » dung tren
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc dan, thuc day
cuu tre » cua tre, cau tren, cau treo
thuc xa » thuc xay, tuc xa, thuc ha
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang ma hoi. hieu van nam ((thuc xa) or (thuc va)) hanh tai ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ma hoi. hieu van nam ((thuc xa) OR (thuc va)) hanh tai ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ma hoi. hieu van nam ((thuc xa) or (thuc va)) hanh tai ((dua tren) or (cuu tre))*.