Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
ty lang » tay lang, ty hang, tu lang
van cam » van nam, van lam, van cau
cam tuc » cam xuc, cam tu, nam thuc
va lanh » va lang, va danh, va hanh
cua tre » cuu tre, cua triet, dua tren
tuc va » thuc va, truc va, tuc xa
cua te » cua tu

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 lang) or (ty xang)) xa hoi. hieu van cam tuc va lanh dao ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty lang) OR (ty xang)) xa hoi. hieu van cam tuc va lanh dao ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty lang) or (ty xang)) xa hoi. hieu van cam tuc va lanh dao ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty lang) or (ty xang)) xa hoi. hieu van cam tuc va lanh dao ((cua tre) OR (cua te))*.