Perhaps you should try some spelling variations:
thanh lai » thanh hai, thanh lap, thanh loi
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
ky sang » ky dang, ky tang, duy sang
mai hoi » mai khoi, dai hoi, lai hoi
cam duc » cao duc, pham duc, nam duoc
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ((ky sang) OR (ky nang)) mai hoi. hieu van ((cam duc) or (cam xuc)) va thanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ((ky sang) OR (ky nang)) mai hoi. hieu van ((cam duc) OR (cam xuc)) va thanh lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ((ky sang) OR (ky nang)) mai hoi. hieu van ((cam duc) or (cam xuc)) va thanh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu cac ((ky sang) OR (ky nang)) mai hoi. hieu van ((cam duc) or (cam xuc)) va thanh lai cua tre*.