Perhaps you should try some spelling variations:
nhanh hai » nhanh thai, thanh hai, nhanh ha
nang dai » nang tai, lang dai, nang cai
nang dau » hang dau, xang dau, nang du
hanh hai » thanh hai, hang hai, hanh tai
su sach » so sach, vu sach
cua tre » cua te, cuu tre, cua triet
cam luc » cam xuc, cau luc
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
luc va » duc va, tuc va, loc va
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((nang dai) or (nang dau)) hoi. hieu ve cam luc va ((hanh hai) OR (nhanh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang dai) OR (nang dau)) hoi. hieu ve cam luc va ((hanh hai) OR (nhanh hai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang dai) or (nang dau)) hoi. hieu ve cam luc va ((hanh hai) OR (nhanh hai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang dai) or (nang dau)) hoi. hieu ve cam luc va ((hanh hai) OR (nhanh hai)) cua tre*.