Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » hieu va, thien van, lieu va
tinh va » tich va, trinh van, tinh gia
van cam » van nam, van lam, van cau
ty hang » ly hang, ty xang, thi hang
ly nang » ky nang, ly hang, ly vang
cuu tre » cua tre, cau tren, cau treo
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ((ly nang) or (ty hang)) xa hoi. hieu van cam xuc va ((tinh va) OR (trinh vat)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((ly nang) OR (ty hang)) xa hoi. hieu van cam xuc va ((tinh va) OR (trinh vat)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((ly nang) or (ty hang)) xa hoi. hieu van cam xuc va ((tinh va) OR (trinh vat)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((ly nang) or (ty hang)) xa hoi. hieu van cam xuc va ((tinh va) OR (trinh vat)) cuu tre*.