Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tinh lai » tinh lao, tinh hai, minh lai
tu sach » thu sach, su sach, te sach
cua tre » cua te, cua triet, dua tren
va tinh » may tinh
cac xuc » cam xuc, cac nuoc, chat xuc
van cac » van hac, van cau, van bac
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
cuu tre » cau tren, cau treo
xuc va » duc va, tuc va, luc va
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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 ty nang ((x hoi) or (o hoi)). hieu van cac xuc va tinh lai ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((x hoi) OR (o hoi)). hieu van cac xuc va tinh lai ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((x hoi) or (o hoi)). hieu van cac xuc va tinh lai ((cua tre) or (cuu tre))*.