Perhaps you should try some spelling variations:
hinh thai » sinh thai, tinh thai, dinh thi
hieu van » hieu va, thien van, lieu va
thai cua » than cua, tai cuc, tri cua
duc van » duc va, duc tan, duc manh
luc van » luoc van, luu van, luc va
so sach » so sanh, bo sach, co sach
van cam » van nam, van lam, van cau
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((y nang) or (ly nang)) o hai. hieu van cam ((luc van) or (duc van)) hinh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((y nang) OR (ly nang)) o hai. hieu van cam ((luc van) OR (duc van)) hinh thai cua tre.
• Adding a wildcard symbol may retrieve word variants: so sach ((y nang) or (ly nang)) o hai. hieu van cam ((luc van) or (duc van)) hinh thai cua tre*.