Perhaps you should try some spelling variations:
thuc van » thuc vat, thuc va, thuc hanh
thuc dan » thuc hanh, hoc dan, thuc vat
thanh di » thanh doi, thanh de, thanh do
su sach » so sach, vu sach
ly nang » ky nang, ly hang, ly vang
cuu tre » cua tre, cau tren, cau treo
va dau » va dao
di cuu » di cau, di cua, dinh cuu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((ly nang) or (ty xang)) xa hoi. lieu va dau ((thuc van) OR (thuc dan)) thanh di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ly nang) OR (ty xang)) xa hoi. lieu va dau ((thuc van) OR (thuc dan)) thanh di cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ly nang) or (ty xang)) xa hoi. lieu va dau ((thuc van) OR (thuc dan)) thanh di cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((ly nang) or (ty xang)) xa hoi. lieu va dau ((thuc van) OR (thuc dan)) thanh di cuu tre*.