Perhaps you should try some spelling variations:
te sach » toc sach
cac dac » cac dan, cac dai, cac bac
dai huu » dao huu, dai hau, dai thua
dai cuu » dai cua
cac duc » cac du, cao duc, cac nuoc
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y nang ma hoi. hieu ve ((cac duc) or (cac dac)) gia thanh ((dai cuu) OR (dai huu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ma hoi. hieu ve ((cac duc) OR (cac dac)) gia thanh ((dai cuu) OR (dai huu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ma hoi. hieu ve ((cac duc) or (cac dac)) gia thanh ((dai cuu) OR (dai huu)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ma hoi. hieu ve ((cac duc) or (cac dac)) gia thanh ((dai cuu) OR (dai huu)) tre*.