Perhaps you should try some spelling variations:
nhanh thi » nhanh thai, nhanh thuc, nhan tai
quoc ban » quoc bao, quoc lan, quoc quan
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
thi cua » thai cua, thi cuc, tri cua
duc van » duc va, duc tan, duc manh
xuc ban » duc ban, cuc ban, xuat ban
sach ty » sach y, sach tu, sach thu
van cac » van hac, van cau, van bac
nang ho » nang hoc, nang co, tang ho
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
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 ty nang ho hai. hieu van cac ((((xuc ban) or (quoc ban))) or (duc van)) nhanh thi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ho hai. hieu van cac ((((xuc ban) OR (quoc ban))) OR (duc van)) nhanh thi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ho hai. hieu van cac ((((xuc ban) or (quoc ban))) or (duc van)) nhanh thi cua tre*.