Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
thanh tai » thanh toan, doanh tai, thanh san
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
cao suc » cao su, cao duc
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
lang ha » long ha
tang ma » mang may, tang van
suc va » duc va, tuc va, luc va
va cao » va cac, va co, va dao

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 ((tang ma) or (lang ha)) hoi. hieu va cao suc va ((thanh tai) OR (thanh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((tang ma) OR (lang ha)) hoi. hieu va cao suc va ((thanh tai) OR (thanh hai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((tang ma) or (lang ha)) hoi. hieu va cao suc va ((thanh tai) OR (thanh hai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((tang ma) or (lang ha)) hoi. hieu va cao suc va ((thanh tai) OR (thanh hai)) cua tre*.