Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
ky lang » ky nang, ky tang, tay lang
ky dang » ky nang, ky danh
hieu ve » hieu va, hieu van
dam tuc » dam thuc, dao tuc, nam thuc
dan dai » dat dai, can dai, dan dat
cua tre » cua te, cuu tre, cua triet
dam tu » nam tu, cam tu, tam tu
va dan » ca dan, va dao, va dau

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 ((ky lang) or (ky dang)) xa hoi. hieu ve ((dam tuc) or (dam tu)) va dan dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu ve ((dam tuc) OR (dam tu)) va dan dai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) or (ky dang)) xa hoi. hieu ve ((dam tuc) or (dam tu)) va dan dai cua tre*.