Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
hanh vai » hanh vi, hanh va, hanh tai
thu sach » thuat sach, thuoc sach, thu hoach
nang tai » hang tai, tang tai, sang tai
vien dai » hien dai
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
dai tuc » dai thuc, dai truc, dao tuc
tu sach » su sach, tu cach, vu sach
tai hai » thi hai, dai hai, tai ha
te sach » toc sach
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa

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) OR (te sach))) or (thu sach)) ky nang tai hai. hieu vien dai tuc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((tu sach) OR (te sach))) OR (thu sach)) ky nang tai hai. hieu vien dai tuc va hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((tu sach) OR (te sach))) or (thu sach)) ky nang tai hai. hieu vien dai tuc va hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((((tu sach) OR (te sach))) or (thu sach)) ky nang tai hai. hieu vien dai tuc va hanh vai cua tre*.