Perhaps you should try some spelling variations:
van chat » cao chat
hieu van » hieu va, thien van, lieu va
chat huu » pham huu
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
huu cam » huu lam, huu tam, huu chau
cam dan » cac dan, ca dan, nam dan
dan vai » dan va, dan tai, dan vat
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
x hoi » xa hoi, o hoi, 5 hoi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang ((x hoi) or (x ho)). hieu van chat huu cam dan vai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((x hoi) OR (x ho)). hieu van chat huu cam dan vai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ((x hoi) or (x ho)). hieu van chat huu cam dan vai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((x hoi) or (x ho)). hieu van chat huu cam dan vai ((cua tre) OR (cuu tre))*.