Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
hieu van » hieu va, thien van, lieu va
thai cua » than cua, tai cuc, tri cua
tu sach » thu sach, su sach, te sach
nang ho » nang hoc, nang co, tang ho
van cac » van hac, van cau, van bac
duc ban » dua ban, duc man, duc manh
duc van » duc va, duc manh, duc phan
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ho hai » hoc hai, pho hai, cho hai

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 ho hai. hieu van cac ((((duc ban) OR (duc tan))) or (duc van)) hanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ho hai. hieu van cac ((((duc ban) OR (duc tan))) OR (duc van)) hanh thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang ho hai. hieu van cac ((((duc ban) OR (duc tan))) or (duc van)) hanh thai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ho hai. hieu van cac ((((duc ban) OR (duc tan))) or (duc van)) hanh thai cua tre*.