Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
xang cao » nang cao, lang cao, quang cao
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, su sach, te sach
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
sach ty » sach y, sach tu, sach thu
cao hoi » cau hoi, co hoi, cao hoc
luc va » tuc va, loc va
ve cac » va cac

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 xang cao hoi. hieu ((ve cac) OR (vien cac)) ((luc va) or (duc va)) hanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty xang cao hoi. hieu ((ve cac) OR (vien cac)) ((luc va) OR (duc va)) hanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty xang cao hoi. hieu ((ve cac) OR (vien cac)) ((luc va) or (duc va)) hanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty xang cao hoi. hieu ((ve cac) OR (vien cac)) ((luc va) or (duc va)) hanh vai cuu tre*.